Repository: GuillaumeGomez/sysinfo (rust)

Issue:
Add some way to remove a closed process
I'm attaching to specific individual processes and want to know when they are closed, so I use 
```rust
if system.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new()) == 0 {
    ...
}
```
to check for that situation. Unfortunately as stated by the documentation, this does not remove it from the entire list of processes. This means I need to run
```rust
system.refresh_processes_specifics(
    ProcessesToUpdate::All,
    ProcessRefreshKind::new().with_exe(UpdateKind::OnlyIfNotSet),
);
```
inside to ensure it gets removed. This is very wasteful. I'd appreciate some sort of way for me to either manually remove it from the list or some argument I can pass / config I can set, so it gets removed properly.

Though arguably the entire default seems questionable to me too.

Pull request description:
Update `System::refresh_processes` API to give control over when to remove dead processes
Fixes #1340.

Patch:
diff --git a/benches/basic.rs b/benches/basic.rs
index 4d0f22f..2853b1b 100644
--- a/benches/basic.rs
+++ b/benches/basic.rs
@@ -33,9 +33,9 @@ fn bench_refresh_all(b: &mut test::Bencher) {
 fn bench_refresh_processes(b: &mut test::Bencher) {
     let mut s = sysinfo::System::new();
 
-    s.refresh_processes(sysinfo::ProcessesToUpdate::All); // to load the whole processes list a first time.
+    s.refresh_processes(sysinfo::ProcessesToUpdate::All, true); // to load the whole processes list a first time.
     b.iter(move || {
-        s.refresh_processes(sysinfo::ProcessesToUpdate::All);
+        s.refresh_processes(sysinfo::ProcessesToUpdate::All, true);
     });
 }
 
@@ -44,7 +44,7 @@ fn bench_refresh_processes(b: &mut test::Bencher) {
 fn bench_first_refresh_processes(b: &mut test::Bencher) {
     b.iter(move || {
         let mut s = sysinfo::System::new();
-        s.refresh_processes(sysinfo::ProcessesToUpdate::All);
+        s.refresh_processes(sysinfo::ProcessesToUpdate::All, true);
     });
 }
 
@@ -57,7 +57,7 @@ fn bench_refresh_process(b: &mut test::Bencher) {
     // to be sure it'll exist for at least as long as we run
     let pid = sysinfo::get_current_pid().expect("failed to get current pid");
     b.iter(move || {
-        s.refresh_processes(sysinfo::ProcessesToUpdate::Some(&[pid]));
+        s.refresh_processes(sysinfo::ProcessesToUpdate::Some(&[pid]), true);
     });
 }
 
diff --git a/examples/simple.rs b/examples/simple.rs
index 5a67183..efd003f 100644
--- a/examples/simple.rs
+++ b/examples/simple.rs
@@ -408,7 +408,7 @@ fn interpret_input(
                     .take(1)
                     .next()
                 {
-                    if sys.refresh_processes(sysinfo::ProcessesToUpdate::Some(&[pid])) != 0 {
+                    if sys.refresh_processes(sysinfo::ProcessesToUpdate::Some(&[pid]), true) != 0 {
                         writeln!(&mut io::stdout(), "Process `{pid}` updated successfully");
                     } else {
                         writeln!(&mut io::stdout(), "Process `{pid}` couldn't be updated...");
diff --git a/src/c_interface.rs b/src/c_interface.rs
index 592949a..c1d007f 100644
--- a/src/c_interface.rs
+++ b/src/c_interface.rs
@@ -54,7 +54,7 @@ pub extern "C" fn sysinfo_refresh_memory(system: CSystem) {
             let system: &mut System = system.borrow_mut();
             system.refresh_memory();
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -68,7 +68,7 @@ pub extern "C" fn sysinfo_refresh_cpu(system: CSystem) {
             let system: &mut System = system.borrow_mut();
             system.refresh_cpu_usage();
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -82,7 +82,7 @@ pub extern "C" fn sysinfo_refresh_all(system: CSystem) {
             let system: &mut System = system.borrow_mut();
             system.refresh_all();
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -96,9 +96,9 @@ pub extern "C" fn sysinfo_refresh_processes(system: CSystem) {
         let mut system: Box<System> = Box::from_raw(system as *mut System);
         {
             let system: &mut System = system.borrow_mut();
-            system.refresh_processes(ProcessesToUpdate::All);
+            system.refresh_processes(ProcessesToUpdate::All, true);
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -112,9 +112,9 @@ pub extern "C" fn sysinfo_refresh_process(system: CSystem, pid: PID) {
         let mut system: Box<System> = Box::from_raw(system as *mut System);
         {
             let system: &mut System = system.borrow_mut();
-            system.refresh_processes(ProcessesToUpdate::Some(&[Pid::from_u32(pid as _)]));
+            system.refresh_processes(ProcessesToUpdate::Some(&[Pid::from_u32(pid as _)]), true);
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -144,7 +144,7 @@ pub extern "C" fn sysinfo_disks_refresh(disks: CDisks) {
             let disks: &mut Disks = disks.borrow_mut();
             disks.refresh();
         }
-        Box::into_raw(disks);
+        let _ = Box::into_raw(disks);
     }
 }
 
@@ -158,7 +158,7 @@ pub extern "C" fn sysinfo_disks_refresh_list(disks: CDisks) {
             let disks: &mut Disks = disks.borrow_mut();
             disks.refresh_list();
         }
-        Box::into_raw(disks);
+        let _ = Box::into_raw(disks);
     }
 }
 
@@ -169,7 +169,7 @@ pub extern "C" fn sysinfo_total_memory(system: CSystem) -> size_t {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let ret = system.total_memory() as size_t;
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -181,7 +181,7 @@ pub extern "C" fn sysinfo_free_memory(system: CSystem) -> size_t {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let ret = system.free_memory() as size_t;
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -192,7 +192,7 @@ pub extern "C" fn sysinfo_used_memory(system: CSystem) -> size_t {
     assert!(!system.is_null());
     let system: Box<System> = unsafe { Box::from_raw(system as *mut System) };
     let ret = system.used_memory() as size_t;
-    Box::into_raw(system);
+    let _ = Box::into_raw(system);
     ret
 }
 
@@ -203,7 +203,7 @@ pub extern "C" fn sysinfo_total_swap(system: CSystem) -> size_t {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let ret = system.total_swap() as size_t;
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -215,7 +215,7 @@ pub extern "C" fn sysinfo_free_swap(system: CSystem) -> size_t {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let ret = system.free_swap() as size_t;
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -227,7 +227,7 @@ pub extern "C" fn sysinfo_used_swap(system: CSystem) -> size_t {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let ret = system.used_swap() as size_t;
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -258,7 +258,7 @@ pub extern "C" fn sysinfo_networks_refresh_list(networks: CNetworks) {
             let networks: &mut Networks = networks.borrow_mut();
             networks.refresh_list();
         }
-        Box::into_raw(networks);
+        let _ = Box::into_raw(networks);
     }
 }
 
@@ -272,7 +272,7 @@ pub extern "C" fn sysinfo_networks_refresh(networks: CNetworks) {
             let networks: &mut Networks = networks.borrow_mut();
             networks.refresh();
         }
-        Box::into_raw(networks);
+        let _ = Box::into_raw(networks);
     }
 }
 
@@ -286,7 +286,7 @@ pub extern "C" fn sysinfo_networks_received(networks: CNetworks) -> size_t {
         let ret = networks.iter().fold(0, |acc: size_t, (_, data)| {
             acc.saturating_add(data.received() as size_t)
         });
-        Box::into_raw(networks);
+        let _ = Box::into_raw(networks);
         ret
     }
 }
@@ -301,7 +301,7 @@ pub extern "C" fn sysinfo_networks_transmitted(networks: CNetworks) -> size_t {
         let ret = networks.iter().fold(0, |acc: size_t, (_, data)| {
             acc.saturating_add(data.transmitted() as size_t)
         });
-        Box::into_raw(networks);
+        let _ = Box::into_raw(networks);
         ret
     }
 }
@@ -333,7 +333,7 @@ pub extern "C" fn sysinfo_cpus_usage(
             }
             *length = cpus.len() as c_uint - 1;
         }
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
     }
 }
 
@@ -362,7 +362,7 @@ pub extern "C" fn sysinfo_processes(
                 }
                 entries.len() as size_t
             };
-            Box::into_raw(system);
+            let _ = Box::into_raw(system);
             len
         }
     } else {
@@ -386,7 +386,7 @@ pub extern "C" fn sysinfo_process_by_pid(system: CSystem, pid: PID) -> CProcess
         } else {
             std::ptr::null()
         };
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         ret
     }
 }
@@ -534,7 +534,7 @@ pub extern "C" fn sysinfo_cpu_vendor_id(system: CSystem) -> RString {
         } else {
             std::ptr::null()
         };
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         c_string
     }
 }
@@ -554,7 +554,7 @@ pub extern "C" fn sysinfo_cpu_brand(system: CSystem) -> RString {
         } else {
             std::ptr::null()
         };
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         c_string
     }
 }
@@ -566,7 +566,7 @@ pub extern "C" fn sysinfo_cpu_physical_cores(system: CSystem) -> u32 {
     unsafe {
         let system: Box<System> = Box::from_raw(system as *mut System);
         let count = system.physical_core_count().unwrap_or(0);
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         count as u32
     }
 }
@@ -582,7 +582,7 @@ pub extern "C" fn sysinfo_cpu_frequency(system: CSystem) -> u64 {
             .first()
             .map(|cpu| cpu.frequency())
             .unwrap_or(0);
-        Box::into_raw(system);
+        let _ = Box::into_raw(system);
         freq
     }
 }
diff --git a/src/common/system.rs b/src/common/system.rs
index 0e42628..588b8c0 100644
--- a/src/common/system.rs
+++ b/src/common/system.rs
@@ -107,7 +107,7 @@ impl System {
             self.refresh_cpu_specifics(kind);
         }
         if let Some(kind) = refreshes.processes() {
-            self.refresh_processes_specifics(ProcessesToUpdate::All, kind);
+            self.refresh_processes_specifics(ProcessesToUpdate::All, false, kind);
         }
     }
 
@@ -262,6 +262,7 @@ impl System {
     /// # let mut system = System::new();
     /// system.refresh_processes_specifics(
     ///     ProcessesToUpdate::All,
+    ///     true,
     ///     ProcessRefreshKind::new()
     ///         .with_memory()
     ///         .with_cpu()
@@ -270,8 +271,9 @@ impl System {
     /// );
     /// ```
     ///
-    /// ⚠️ Unless `ProcessesToUpdate::All` is used, dead processes are not removed from
-    /// the set of processes kept in [`System`].
+    /// ⚠️ `remove_dead_processes` works as follows: if an updated process is dead, then it is
+    /// removed. So if you refresh pids 1, 2 and 3. If 2 and 7 are dead, only 2 will be removed
+    /// since 7 is not part of the update.
     ///
     /// ⚠️ On Linux, `sysinfo` keeps the `stat` files open by default. You can change this behaviour
     /// by using [`set_open_files_limit`][crate::set_open_files_limit].
@@ -282,11 +284,16 @@ impl System {
     /// use sysinfo::{ProcessesToUpdate, System};
     ///
     /// let mut s = System::new_all();
-    /// s.refresh_processes(ProcessesToUpdate::All);
+    /// s.refresh_processes(ProcessesToUpdate::All, true);
     /// ```
-    pub fn refresh_processes(&mut self, processes_to_update: ProcessesToUpdate<'_>) -> usize {
+    pub fn refresh_processes(
+        &mut self,
+        processes_to_update: ProcessesToUpdate<'_>,
+        remove_dead_processes: bool,
+    ) -> usize {
         self.refresh_processes_specifics(
             processes_to_update,
+            remove_dead_processes,
             ProcessRefreshKind::new()
                 .with_memory()
                 .with_cpu()
@@ -299,8 +306,9 @@ impl System {
     ///
     /// Returns the number of updated processes.
     ///
-    /// ⚠️ Unless `ProcessesToUpdate::All` is used, dead processes are not removed from
-    /// the set of processes kept in [`System`].
+    /// ⚠️ `remove_dead_processes` works as follows: if an updated process is dead, then it is
+    /// removed. So if you refresh pids 1, 2 and 3. If 2 and 7 are dead, only 2 will be removed
+    /// since 7 is not part of the update.
     ///
     /// ⚠️ On Linux, `sysinfo` keeps the `stat` files open by default. You can change this behaviour
     /// by using [`set_open_files_limit`][crate::set_open_files_limit].
@@ -309,15 +317,60 @@ impl System {
     /// use sysinfo::{ProcessesToUpdate, ProcessRefreshKind, System};
     ///
     /// let mut s = System::new_all();
-    /// s.refresh_processes_specifics(ProcessesToUpdate::All, ProcessRefreshKind::new());
+    /// s.refresh_processes_specifics(
+    ///     ProcessesToUpdate::All,
+    ///     true,
+    ///     ProcessRefreshKind::everything(),
+    /// );
     /// ```
     pub fn refresh_processes_specifics(
         &mut self,
         processes_to_update: ProcessesToUpdate<'_>,
+        remove_dead_processes: bool,
         refresh_kind: ProcessRefreshKind,
     ) -> usize {
-        self.inner
-            .refresh_processes_specifics(processes_to_update, refresh_kind)
+        fn update_and_remove(pid: &Pid, processes: &mut HashMap<Pid, Process>) {
+            let updated = if let Some(proc) = processes.get_mut(pid) {
+                proc.inner.switch_updated()
+            } else {
+                return;
+            };
+            if !updated {
+                processes.remove(pid);
+            }
+        }
+        fn update(pid: &Pid, processes: &mut HashMap<Pid, Process>) {
+            if let Some(proc) = processes.get_mut(pid) {
+                proc.inner.switch_updated();
+            }
+        }
+
+        let nb_updated = self
+            .inner
+            .refresh_processes_specifics(processes_to_update, refresh_kind);
+        let processes = self.inner.processes_mut();
+        match processes_to_update {
+            ProcessesToUpdate::All => {
+                if remove_dead_processes {
+                    processes.retain(|_, v| v.inner.switch_updated());
+                } else {
+                    for proc in processes.values_mut() {
+                        proc.inner.switch_updated();
+                    }
+                }
+            }
+            ProcessesToUpdate::Some(pids) => {
+                let call = if remove_dead_processes {
+                    update_and_remove
+                } else {
+                    update
+                };
+                for pid in pids {
+                    call(pid, processes);
+                }
+            }
+        }
+        nb_updated
     }
 
     /// Returns the process list.
@@ -1371,6 +1424,7 @@ impl Process {
     /// // Refresh CPU usage to get actual value.
     /// s.refresh_processes_specifics(
     ///     ProcessesToUpdate::All,
+    ///     true,
     ///     ProcessRefreshKind::new().with_cpu()
     /// );
     /// if let Some(process) = s.process(Pid::from(1337)) {
@@ -1844,6 +1898,7 @@ assert_eq!(r.", stringify!($name), "().is_some(), false);
 /// let mut system = System::new();
 /// system.refresh_processes_specifics(
 ///     ProcessesToUpdate::All,
+///     true,
 ///     ProcessRefreshKind::new().with_exe(UpdateKind::OnlyIfNotSet),
 /// );
 /// ```
@@ -1880,11 +1935,12 @@ impl UpdateKind {
 ///
 /// let mut system = System::new();
 /// // To refresh all processes:
-/// system.refresh_processes(ProcessesToUpdate::All);
+/// system.refresh_processes(ProcessesToUpdate::All, true);
 ///
 /// // To refresh only the current one:
 /// system.refresh_processes(
 ///     ProcessesToUpdate::Some(&[get_current_pid().unwrap()]),
+///     true,
 /// );
 /// ```
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -1917,6 +1973,7 @@ pub enum ProcessesToUpdate<'a> {
 /// // We don't want to update the CPU information.
 /// system.refresh_processes_specifics(
 ///     ProcessesToUpdate::All,
+///     true,
 ///     ProcessRefreshKind::everything().without_cpu(),
 /// );
 ///
@@ -2393,7 +2450,7 @@ mod test {
         }
         let mut s = System::new_all();
         let total = s.processes().len() as isize;
-        s.refresh_processes(ProcessesToUpdate::All);
+        s.refresh_processes(ProcessesToUpdate::All, false);
         let new_total = s.processes().len() as isize;
         // There should be almost no difference in the processes count.
         assert!(
@@ -2415,7 +2472,7 @@ mod test {
             return;
         }
         let mut s = System::new();
-        s.refresh_processes(ProcessesToUpdate::All);
+        s.refresh_processes(ProcessesToUpdate::All, false);
         for proc_ in s.cpus() {
             assert_eq!(proc_.frequency(), 0);
         }
@@ -2490,7 +2547,7 @@ mod test {
         }
         let mut s = System::new();
 
-        s.refresh_processes(ProcessesToUpdate::All);
+        s.refresh_processes(ProcessesToUpdate::All, false);
         // All CPU usage will start at zero until the second refresh
         assert!(s
             .processes()
@@ -2499,7 +2556,7 @@ mod test {
 
         // Wait a bit to update CPU usage values
         std::thread::sleep(MINIMUM_CPU_UPDATE_INTERVAL);
-        s.refresh_processes(ProcessesToUpdate::All);
+        s.refresh_processes(ProcessesToUpdate::All, true);
         assert!(s
             .processes()
             .iter()
@@ -2571,9 +2628,15 @@ mod test {
             {
                 let mut s = System::new();
                 // First check what happens in case the process isn't already in our process list.
-                assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[_pid])), 1);
+                assert_eq!(
+                    s.refresh_processes(ProcessesToUpdate::Some(&[_pid]), true),
+                    1
+                );
                 // Then check that it still returns 1 if the process is already in our process list.
-                assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[_pid])), 1);
+                assert_eq!(
+                    s.refresh_processes(ProcessesToUpdate::Some(&[_pid]), true),
+                    1
+                );
             }
         }
     }
diff --git a/src/unix/apple/app_store/process.rs b/src/unix/apple/app_store/process.rs
index e23c749..0a52ef6 100644
--- a/src/unix/apple/app_store/process.rs
+++ b/src/unix/apple/app_store/process.rs
@@ -93,4 +93,8 @@ impl ProcessInner {
     pub(crate) fn session_id(&self) -> Option<Pid> {
         None
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+        false
+    }
 }
diff --git a/src/unix/apple/macos/process.rs b/src/unix/apple/macos/process.rs
index 27d1655..08a33dd 100644
--- a/src/unix/apple/macos/process.rs
+++ b/src/unix/apple/macos/process.rs
@@ -226,6 +226,10 @@ impl ProcessInner {
             }
         }
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+         std::mem::replace(&mut self.updated, false)
+    }
 }
 
 #[allow(deprecated)] // Because of libc::mach_absolute_time.
diff --git a/src/unix/apple/system.rs b/src/unix/apple/system.rs
index 77aaf84..2d5014f 100644
--- a/src/unix/apple/system.rs
+++ b/src/unix/apple/system.rs
@@ -260,17 +260,16 @@ impl SystemInner {
             }
 
             #[allow(clippy::type_complexity)]
-            let (filter, filter_callback, remove_processes): (
+            let (filter, filter_callback): (
                 &[Pid],
                 &(dyn Fn(Pid, &[Pid]) -> bool + Sync + Send),
-                bool,
             ) = match processes_to_update {
-                ProcessesToUpdate::All => (&[], &empty_filter, true),
+                ProcessesToUpdate::All => (&[], &empty_filter),
                 ProcessesToUpdate::Some(pids) => {
                     if pids.is_empty() {
                         return 0;
                     }
-                    (pids, &real_filter, false)
+                    (pids, &real_filter)
                 }
             };
 
@@ -298,10 +297,6 @@ impl SystemInner {
             entries.into_iter().for_each(|entry| {
                 self.process_list.insert(entry.pid(), entry);
             });
-            if remove_processes {
-                self.process_list
-                    .retain(|_, proc_| std::mem::replace(&mut proc_.inner.updated, false));
-            }
             nb_updated.into_inner()
         } else {
             0
@@ -316,6 +311,10 @@ impl SystemInner {
         &self.process_list
     }
 
+    pub(crate) fn processes_mut(&mut self) -> &mut HashMap<Pid, Process> {
+        &mut self.process_list
+    }
+
     pub(crate) fn process(&self, pid: Pid) -> Option<&Process> {
         self.process_list.get(&pid)
     }
diff --git a/src/unix/freebsd/process.rs b/src/unix/freebsd/process.rs
index 3abc348..ac946e7 100644
--- a/src/unix/freebsd/process.rs
+++ b/src/unix/freebsd/process.rs
@@ -178,6 +178,10 @@ impl ProcessInner {
             }
         }
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+         std::mem::replace(&mut self.updated, false)
+    }
 }
 
 pub(crate) unsafe fn get_process_data(
@@ -293,7 +297,7 @@ pub(crate) unsafe fn get_process_data(
             old_read_bytes: 0,
             written_bytes: kproc.ki_rusage.ru_oublock as _,
             old_written_bytes: 0,
-            updated: false,
+            updated: true,
         },
     }))
 }
diff --git a/src/unix/freebsd/system.rs b/src/unix/freebsd/system.rs
index 80d4c5e..74ba25c 100644
--- a/src/unix/freebsd/system.rs
+++ b/src/unix/freebsd/system.rs
@@ -131,6 +131,10 @@ impl SystemInner {
         &self.process_list
     }
 
+    pub(crate) fn processes_mut(&mut self) -> &mut HashMap<Pid, Process> {
+        &mut self.process_list
+    }
+
     pub(crate) fn process(&self, pid: Pid) -> Option<&Process> {
         self.process_list.get(&pid)
     }
@@ -294,17 +298,16 @@ impl SystemInner {
         }
 
         #[allow(clippy::type_complexity)]
-        let (filter, filter_callback, remove_processes): (
+        let (filter, filter_callback): (
             &[Pid],
             &(dyn Fn(&libc::kinfo_proc, &[Pid]) -> bool + Sync + Send),
-            bool,
         ) = match processes_to_update {
-            ProcessesToUpdate::All => (&[], &empty_filter, true),
+            ProcessesToUpdate::All => (&[], &empty_filter),
             ProcessesToUpdate::Some(pids) => {
                 if pids.is_empty() {
                     return 0;
                 }
-                (pids, &real_filter, false)
+                (pids, &real_filter)
             }
         };
 
@@ -343,12 +346,6 @@ impl SystemInner {
             .collect::<Vec<_>>()
         };
 
-        if remove_processes {
-            // We remove all processes that don't exist anymore.
-            self.process_list
-                .retain(|_, v| std::mem::replace(&mut v.inner.updated, false));
-        }
-
         for process in new_processes {
             self.process_list.insert(process.inner.pid, process);
         }
diff --git a/src/unix/linux/process.rs b/src/unix/linux/process.rs
index f3438a9..cd2a5d0 100644
--- a/src/unix/linux/process.rs
+++ b/src/unix/linux/process.rs
@@ -278,6 +278,10 @@ impl ProcessInner {
     pub(crate) fn thread_kind(&self) -> Option<ThreadKind> {
         self.thread_kind
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+         std::mem::replace(&mut self.updated, false)
+    }
 }
 
 pub(crate) fn compute_cpu_usage(p: &mut ProcessInner, total_time: f32, max_value: f32) {
@@ -297,10 +301,6 @@ pub(crate) fn compute_cpu_usage(p: &mut ProcessInner, total_time: f32, max_value
         .min(max_value);
 }
 
-pub(crate) fn unset_updated(p: &mut ProcessInner) {
-    p.updated = false;
-}
-
 pub(crate) fn set_time(p: &mut ProcessInner, utime: u64, stime: u64) {
     p.old_utime = p.utime;
     p.old_stime = p.stime;
diff --git a/src/unix/linux/system.rs b/src/unix/linux/system.rs
index 1112dfb..33001e0 100644
--- a/src/unix/linux/system.rs
+++ b/src/unix/linux/system.rs
@@ -1,7 +1,7 @@
 // Take a look at the license at the top of the repository in the LICENSE file.
 
 use crate::sys::cpu::{get_physical_core_count, CpusWrapper};
-use crate::sys::process::{compute_cpu_usage, refresh_procs, unset_updated};
+use crate::sys::process::{compute_cpu_usage, refresh_procs};
 use crate::sys::utils::{get_all_utf8_data, to_u64};
 use crate::{Cpu, CpuRefreshKind, LoadAvg, MemoryRefreshKind, Pid, Process, ProcessesToUpdate, ProcessRefreshKind};
 
@@ -173,38 +173,24 @@ impl SystemInner {
         self.cpus.len() as f32 * 100.
     }
 
-    fn clear_procs(&mut self, refresh_kind: ProcessRefreshKind) {
-        let (total_time, compute_cpu, max_value) = if refresh_kind.cpu() {
-            self.cpus
-                .refresh_if_needed(true, CpuRefreshKind::new().with_cpu_usage());
+    fn update_procs_cpu(&mut self, refresh_kind: ProcessRefreshKind) {
+        if !refresh_kind.cpu() {
+            return;
+        }
+        self.cpus.refresh_if_needed(true, CpuRefreshKind::new().with_cpu_usage());
 
-            if self.cpus.is_empty() {
-                sysinfo_debug!("cannot compute processes CPU usage: no CPU found...");
-                (0., false, 0.)
-            } else {
-                let (new, old) = self.cpus.get_global_raw_times();
-                let total_time = if old > new { 1 } else { new - old };
-                (
-                    total_time as f32 / self.cpus.len() as f32,
-                    true,
-                    self.get_max_process_cpu_usage(),
-                )
-            }
-        } else {
-            (0., false, 0.)
-        };
+        if self.cpus.is_empty() {
+            sysinfo_debug!("cannot compute processes CPU usage: no CPU found...");
+            return;
+        }
+        let (new, old) = self.cpus.get_global_raw_times();
+        let total_time = if old > new { 1 } else { new - old };
+        let total_time = total_time as f32 / self.cpus.len() as f32;
+        let max_value = self.get_max_process_cpu_usage();
 
-        self.process_list.retain(|_, proc_| {
-            let proc_ = &mut proc_.inner;
-            if !proc_.updated {
-                return false;
-            }
-            if compute_cpu {
-                compute_cpu_usage(proc_, total_time, max_value);
-            }
-            unset_updated(proc_);
-            true
-        });
+        for proc_ in self.process_list.values_mut() {
+            compute_cpu_usage(&mut proc_.inner, total_time, max_value);
+        }
     }
 
     fn refresh_cpus(&mut self, only_update_global_cpu: bool, refresh_kind: CpuRefreshKind) {
@@ -291,7 +277,7 @@ impl SystemInner {
             refresh_kind,
         );
         if matches!(processes_to_update, ProcessesToUpdate::All) {
-            self.clear_procs(refresh_kind);
+            self.update_procs_cpu(refresh_kind);
             self.cpus.set_need_cpus_update();
         }
         nb_updated
@@ -305,6 +291,10 @@ impl SystemInner {
         &self.process_list
     }
 
+    pub(crate) fn processes_mut(&mut self) -> &mut HashMap<Pid, Process> {
+        &mut self.process_list
+    }
+
     pub(crate) fn process(&self, pid: Pid) -> Option<&Process> {
         self.process_list.get(&pid)
     }
diff --git a/src/unknown/process.rs b/src/unknown/process.rs
index 00d8e4b..3de87f4 100644
--- a/src/unknown/process.rs
+++ b/src/unknown/process.rs
@@ -103,4 +103,8 @@ impl ProcessInner {
     pub(crate) fn session_id(&self) -> Option<Pid> {
         None
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+        false
+    }
 }
diff --git a/src/unknown/system.rs b/src/unknown/system.rs
index 7395c86..c5a81fa 100644
--- a/src/unknown/system.rs
+++ b/src/unknown/system.rs
@@ -16,13 +16,13 @@ pub const SUPPORTED_SIGNALS: &[crate::Signal] = supported_signals();
 pub const MINIMUM_CPU_UPDATE_INTERVAL: Duration = Duration::from_millis(0);
 
 pub(crate) struct SystemInner {
-    processes_list: HashMap<Pid, Process>,
+    process_list: HashMap<Pid, Process>,
 }
 
 impl SystemInner {
     pub(crate) fn new() -> Self {
         Self {
-            processes_list: Default::default(),
+            process_list: Default::default(),
         }
     }
 
@@ -49,7 +49,11 @@ impl SystemInner {
     // Need to be moved into a "common" file to avoid duplication.
 
     pub(crate) fn processes(&self) -> &HashMap<Pid, Process> {
-        &self.processes_list
+        &self.process_list
+    }
+
+    pub(crate) fn processes_mut(&mut self) -> &mut HashMap<Pid, Process> {
+        &mut self.process_list
     }
 
     pub(crate) fn process(&self, _pid: Pid) -> Option<&Process> {
diff --git a/src/windows/process.rs b/src/windows/process.rs
index 79ff911..e881906 100644
--- a/src/windows/process.rs
+++ b/src/windows/process.rs
@@ -443,6 +443,10 @@ impl ProcessInner {
             None
         }
     }
+
+    pub(crate) fn switch_updated(&mut self) -> bool {
+         std::mem::replace(&mut self.updated, false)
+    }
 }
 
 #[inline]
diff --git a/src/windows/system.rs b/src/windows/system.rs
index 4cce483..a42ed49 100644
--- a/src/windows/system.rs
+++ b/src/windows/system.rs
@@ -10,7 +10,7 @@ use crate::utils::into_iter;
 use std::cell::UnsafeCell;
 use std::collections::HashMap;
 use std::ffi::{OsStr, OsString};
-use std::mem::{replace, size_of, zeroed};
+use std::mem::{size_of, zeroed};
 use std::os::windows::ffi::{OsStrExt, OsStringExt};
 use std::ptr;
 use std::sync::atomic::{AtomicUsize, Ordering};
@@ -199,17 +199,16 @@ impl SystemInner {
         }
 
         #[allow(clippy::type_complexity)]
-        let (filter_array, filter_callback, remove_processes): (
+        let (filter_array, filter_callback): (
             &[Pid],
             &(dyn Fn(Pid, &[Pid]) -> bool + Sync + Send),
-            bool,
         ) = match processes_to_update {
-            ProcessesToUpdate::All => (&[], &empty_filter, true),
+            ProcessesToUpdate::All => (&[], &empty_filter),
             ProcessesToUpdate::Some(pids) => {
                 if pids.is_empty() {
                     return 0;
                 }
-                (pids, &real_filter, false)
+                (pids, &real_filter)
             }
         };
 
@@ -337,11 +336,6 @@ impl SystemInner {
             for p in processes.into_iter() {
                 self.process_list.insert(p.pid(), p);
             }
-            if remove_processes {
-                // If it comes from `refresh_process` or `refresh_pids`, we don't remove
-                // dead processes.
-                self.process_list.retain(|_, v| replace(&mut v.inner.updated, false));
-            }
             nb_updated.into_inner()
         }
     }
@@ -350,6 +344,10 @@ impl SystemInner {
         &self.process_list
     }
 
+    pub(crate) fn processes_mut(&mut self) -> &mut HashMap<Pid, Process> {
+        &mut self.process_list
+    }
+
     pub(crate) fn process(&self, pid: Pid) -> Option<&Process> {
         self.process_list.get(&pid)
     }


Test patch:
diff --git a/tests/process.rs b/tests/process.rs
index 869cddf..8aa2690 100644
--- a/tests/process.rs
+++ b/tests/process.rs
@@ -37,6 +37,7 @@ fn test_cwd() {
     let mut s = System::new();
     s.refresh_processes_specifics(
         ProcessesToUpdate::All,
+        false,
         ProcessRefreshKind::new().with_cwd(UpdateKind::Always),
     );
     p.kill().expect("Unable to kill process.");
@@ -63,6 +64,7 @@ fn test_cmd() {
     assert!(s.processes().is_empty());
     s.refresh_processes_specifics(
         ProcessesToUpdate::All,
+        false,
         ProcessRefreshKind::new().with_cmd(UpdateKind::Always),
     );
     p.kill().expect("Unable to kill process");
@@ -94,6 +96,7 @@ fn build_test_binary(file_name: &str) {
 }
 
 #[test]
+#[allow(clippy::zombie_processes)]
 fn test_environ() {
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") {
         return;
@@ -112,6 +115,7 @@ fn test_environ() {
 
     s.refresh_processes_specifics(
         ProcessesToUpdate::Some(&[pid]),
+        false,
         sysinfo::ProcessRefreshKind::everything(),
     );
     p.kill().expect("Unable to kill process.");
@@ -145,6 +149,7 @@ fn test_environ() {
 
     s.refresh_processes_specifics(
         ProcessesToUpdate::All,
+        false,
         ProcessRefreshKind::new().with_environ(UpdateKind::Always),
     );
 
@@ -169,9 +174,10 @@ fn test_process_refresh() {
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") {
         return;
     }
-    s.refresh_processes(ProcessesToUpdate::Some(&[
-        sysinfo::get_current_pid().expect("failed to get current pid")
-    ]));
+    s.refresh_processes(
+        ProcessesToUpdate::Some(&[sysinfo::get_current_pid().expect("failed to get current pid")]),
+        false,
+    );
     assert!(s
         .process(sysinfo::get_current_pid().expect("failed to get current pid"))
         .is_some());
@@ -213,7 +219,7 @@ fn test_process_disk_usage() {
         std::thread::sleep(std::time::Duration::from_millis(250));
         let mut system = System::new();
         assert!(system.processes().is_empty());
-        system.refresh_processes(ProcessesToUpdate::All);
+        system.refresh_processes(ProcessesToUpdate::All, false);
         assert!(!system.processes().is_empty());
         system
     }
@@ -249,7 +255,7 @@ fn test_process_disk_usage() {
 #[test]
 fn cpu_usage_is_not_nan() {
     let mut system = System::new();
-    system.refresh_processes(ProcessesToUpdate::All);
+    system.refresh_processes(ProcessesToUpdate::All, false);
 
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") {
         return;
@@ -266,7 +272,7 @@ fn cpu_usage_is_not_nan() {
     let mut checked = 0;
 
     first_pids.into_iter().for_each(|pid| {
-        system.refresh_processes(ProcessesToUpdate::Some(&[pid]));
+        system.refresh_processes(ProcessesToUpdate::Some(&[pid]), true);
         if let Some(p) = system.process(pid) {
             assert!(!p.cpu_usage().is_nan());
             checked += 1;
@@ -289,7 +295,7 @@ fn test_process_times() {
     let pid = Pid::from_u32(p.id() as _);
     std::thread::sleep(std::time::Duration::from_secs(1));
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
     p.kill().expect("Unable to kill process.");
 
     if let Some(p) = s.process(pid) {
@@ -319,7 +325,7 @@ fn test_process_session_id() {
         return;
     }
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
     assert!(s.processes().values().any(|p| p.session_id().is_some()));
 }
 
@@ -336,7 +342,7 @@ fn test_refresh_processes() {
 
     // Checks that the process is listed as it should.
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
     assert!(s.process(pid).is_some());
 
     // Check that the process name is not empty.
@@ -348,12 +354,12 @@ fn test_refresh_processes() {
     // Let's give some time to the system to clean up...
     std::thread::sleep(std::time::Duration::from_secs(1));
 
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, true);
     // Checks that the process isn't listed anymore.
     assert!(s.process(pid).is_none());
 }
 
-// This test ensures that if we refresh only one process, then no process is removed.
+// This test ensures that if we refresh only one process, then only this process is removed.
 #[test]
 fn test_refresh_process_doesnt_remove() {
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") {
@@ -370,7 +376,7 @@ fn test_refresh_process_doesnt_remove() {
     let mut s = System::new_with_specifics(
         RefreshKind::new().with_processes(sysinfo::ProcessRefreshKind::new()),
     );
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
 
     assert!(s.process(pid1).is_some());
     assert!(s.process(pid2).is_some());
@@ -384,11 +390,23 @@ fn test_refresh_process_doesnt_remove() {
     // Let's give some time to the system to clean up...
     std::thread::sleep(std::time::Duration::from_secs(1));
 
-    assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[pid1])), 0);
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid1]), false),
+        0
+    );
 
     // We check that none of the two processes were removed.
     assert!(s.process(pid1).is_some());
     assert!(s.process(pid2).is_some());
+
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid1]), true),
+        0
+    );
+
+    // We check that only `pid1` was removed.
+    assert!(s.process(pid1).is_none());
+    assert!(s.process(pid2).is_some());
 }
 
 // Checks that `refresh_processes` is adding and removing task.
@@ -413,7 +431,7 @@ fn test_refresh_tasks() {
 
     // Checks that the task is listed as it should.
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
 
     assert!(s
         .process(pid)
@@ -432,7 +450,7 @@ fn test_refresh_tasks() {
     // Let's give some time to the system to clean up...
     std::thread::sleep(std::time::Duration::from_secs(2));
 
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, true);
 
     assert!(!s
         .process(pid)
@@ -449,7 +467,7 @@ fn test_refresh_tasks() {
         .is_none());
 }
 
-// Checks that `refresh_process` is NOT removing dead processes.
+// Checks that `refresh_process` is removing dead processes when asked.
 #[test]
 fn test_refresh_process() {
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") {
@@ -462,7 +480,7 @@ fn test_refresh_process() {
 
     // Checks that the process is listed as it should.
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::Some(&[pid]));
+    s.refresh_processes(ProcessesToUpdate::Some(&[pid]), false);
     assert!(s.process(pid).is_some());
 
     // Check that the process name is not empty.
@@ -474,9 +492,19 @@ fn test_refresh_process() {
     // Let's give some time to the system to clean up...
     std::thread::sleep(std::time::Duration::from_secs(1));
 
-    assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[pid])), 0);
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid]), false),
+        0
+    );
     // Checks that the process is still listed.
     assert!(s.process(pid).is_some());
+
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid]), true),
+        0
+    );
+    // Checks that the process is not listed anymore.
+    assert!(s.process(pid).is_none());
 }
 
 #[test]
@@ -490,7 +518,7 @@ fn test_wait_child() {
     let pid = Pid::from_u32(p.id() as _);
 
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::Some(&[pid]));
+    s.refresh_processes(ProcessesToUpdate::Some(&[pid]), false);
     let process = s.process(pid).unwrap();
 
     // Kill the child process.
@@ -499,7 +527,10 @@ fn test_wait_child() {
     process.wait();
 
     // Child process should not be present.
-    assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[pid])), 0);
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid]), true),
+        0
+    );
     assert!(before.elapsed() < std::time::Duration::from_millis(1000));
 }
 
@@ -526,14 +557,17 @@ fn test_wait_non_child() {
     let pid = Pid::from_u32(p.id());
 
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::Some(&[pid]));
+    s.refresh_processes(ProcessesToUpdate::Some(&[pid]), false);
     let process = s.process(pid).expect("Process not found!");
 
     // Wait for a non child process.
     process.wait();
 
     // Child process should not be present.
-    assert_eq!(s.refresh_processes(ProcessesToUpdate::Some(&[pid])), 0);
+    assert_eq!(
+        s.refresh_processes(ProcessesToUpdate::Some(&[pid]), true),
+        0
+    );
 
     // should wait for 2s.
     assert!(
@@ -668,13 +702,13 @@ fn test_process_specific_refresh() {
 
     macro_rules! update_specific_and_check {
         (memory) => {
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new());
             {
                 let p = s.process(pid).unwrap();
                 assert_eq!(p.memory(), 0, "failed 0 check for memory");
                 assert_eq!(p.virtual_memory(), 0, "failed 0 check for virtual memory");
             }
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new().with_memory());
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new().with_memory());
             {
                 let p = s.process(pid).unwrap();
                 assert_ne!(p.memory(), 0, "failed non-0 check for memory");
@@ -682,7 +716,7 @@ fn test_process_specific_refresh() {
             }
             // And now we check that re-refreshing nothing won't remove the
             // information.
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new());
             {
                 let p = s.process(pid).unwrap();
                 assert_ne!(p.memory(), 0, "failed non-0 check (number 2) for memory");
@@ -690,7 +724,7 @@ fn test_process_specific_refresh() {
             }
         };
         ($name:ident, $method:ident, $($extra:tt)+) => {
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new());
             {
                 let p = s.process(pid).unwrap();
                 assert_eq!(
@@ -698,7 +732,7 @@ fn test_process_specific_refresh() {
                     concat!("failed 0 check check for ", stringify!($name)),
                 );
             }
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new().$method(UpdateKind::Always));
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new().$method(UpdateKind::Always));
             {
                 let p = s.process(pid).unwrap();
                 assert_ne!(
@@ -707,7 +741,7 @@ fn test_process_specific_refresh() {
             }
             // And now we check that re-refreshing nothing won't remove the
             // information.
-            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+            s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), false, ProcessRefreshKind::new());
             {
                 let p = s.process(pid).unwrap();
                 assert_ne!(
@@ -717,10 +751,18 @@ fn test_process_specific_refresh() {
         }
     }
 
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid]),
+        false,
+        ProcessRefreshKind::new(),
+    );
     check_empty(&s, pid);
 
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid]), ProcessRefreshKind::new());
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid]),
+        false,
+        ProcessRefreshKind::new(),
+    );
     check_empty(&s, pid);
 
     update_specific_and_check!(memory);
@@ -750,7 +792,7 @@ fn test_refresh_pids() {
     let child_pid = Pid::from_u32(p.id() as _);
     let pids = &[child_pid, self_pid];
     std::thread::sleep(std::time::Duration::from_millis(500));
-    s.refresh_processes(ProcessesToUpdate::Some(pids));
+    s.refresh_processes(ProcessesToUpdate::Some(pids), false);
     p.kill().expect("Unable to kill process.");
 
     assert_eq!(s.processes().len(), 2);
@@ -766,10 +808,10 @@ fn test_process_run_time() {
     }
     let mut s = System::new();
     let current_pid = sysinfo::get_current_pid().expect("failed to get current pid");
-    s.refresh_processes(ProcessesToUpdate::Some(&[current_pid]));
+    s.refresh_processes(ProcessesToUpdate::Some(&[current_pid]), false);
     let run_time = s.process(current_pid).expect("no process found").run_time();
     std::thread::sleep(std::time::Duration::from_secs(2));
-    s.refresh_processes(ProcessesToUpdate::Some(&[current_pid]));
+    s.refresh_processes(ProcessesToUpdate::Some(&[current_pid]), true);
     let new_run_time = s.process(current_pid).expect("no process found").run_time();
     assert!(
         new_run_time > run_time,
@@ -799,7 +841,7 @@ fn test_parent_change() {
 
     let pid = Pid::from_u32(p.id() as _);
     let mut s = System::new();
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, false);
 
     assert_eq!(
         s.process(pid).expect("process was not created").parent(),
@@ -816,7 +858,7 @@ fn test_parent_change() {
     // Waiting for the parent process to stop.
     p.wait().expect("wait failed");
 
-    s.refresh_processes(ProcessesToUpdate::All);
+    s.refresh_processes(ProcessesToUpdate::All, true);
     // Parent should not be around anymore.
     assert!(s.process(pid).is_none());
 
@@ -829,7 +871,7 @@ fn test_parent_change() {
 }
 
 // We want to ensure that if `System::refresh_process*` methods are called
-// one after the other, it won't impact the CPU usage computation badly.
+// one after the other, it won't badly impact the CPU usage computation.
 #[test]
 fn test_multiple_single_process_refresh() {
     if !sysinfo::IS_SUPPORTED_SYSTEM || cfg!(feature = "apple-sandbox") || cfg!(windows) {
@@ -853,12 +895,28 @@ fn test_multiple_single_process_refresh() {
 
     let mut s = System::new();
     let process_refresh_kind = ProcessRefreshKind::new().with_cpu();
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid_a]), process_refresh_kind);
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid_b]), process_refresh_kind);
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid_a]),
+        false,
+        process_refresh_kind,
+    );
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid_b]),
+        false,
+        process_refresh_kind,
+    );
 
     std::thread::sleep(std::time::Duration::from_secs(1));
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid_a]), process_refresh_kind);
-    s.refresh_processes_specifics(ProcessesToUpdate::Some(&[pid_b]), process_refresh_kind);
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid_a]),
+        true,
+        process_refresh_kind,
+    );
+    s.refresh_processes_specifics(
+        ProcessesToUpdate::Some(&[pid_b]),
+        true,
+        process_refresh_kind,
+    );
 
     let cpu_a = s.process(pid_a).unwrap().cpu_usage();
     let cpu_b = s.process(pid_b).unwrap().cpu_usage();
diff --git a/tests/system.rs b/tests/system.rs
index 11faf2e..dac837d 100644
--- a/tests/system.rs
+++ b/tests/system.rs
@@ -28,9 +28,12 @@ fn test_refresh_process() {
     #[cfg(not(feature = "apple-sandbox"))]
     if sysinfo::IS_SUPPORTED_SYSTEM {
         assert_eq!(
-            sys.refresh_processes(ProcessesToUpdate::Some(&[
-                sysinfo::get_current_pid().expect("failed to get current pid")
-            ])),
+            sys.refresh_processes(
+                ProcessesToUpdate::Some(&[
+                    sysinfo::get_current_pid().expect("failed to get current pid")
+                ]),
+                false
+            ),
             1,
             "process not listed",
         );
@@ -44,7 +47,7 @@ fn test_refresh_process() {
 #[test]
 fn test_get_process() {
     let mut sys = System::new();
-    sys.refresh_processes(ProcessesToUpdate::All);
+    sys.refresh_processes(ProcessesToUpdate::All, false);
     let current_pid = match sysinfo::get_current_pid() {
         Ok(pid) => pid,
         _ => {
@@ -76,7 +79,7 @@ fn check_if_send_and_sync() {
     impl<T> Bar for T where T: Sync {}
 
     let mut sys = System::new();
-    sys.refresh_processes(ProcessesToUpdate::All);
+    sys.refresh_processes(ProcessesToUpdate::All, false);
     let current_pid = match sysinfo::get_current_pid() {
         Ok(pid) => pid,
         _ => {
@@ -137,7 +140,11 @@ fn test_consecutive_cpu_usage_update() {
 
     let mut sys = System::new_all();
     assert!(!sys.cpus().is_empty());
-    sys.refresh_processes_specifics(ProcessesToUpdate::All, ProcessRefreshKind::new().with_cpu());
+    sys.refresh_processes_specifics(
+        ProcessesToUpdate::All,
+        true,
+        ProcessRefreshKind::new().with_cpu(),
+    );
 
     let stop = Arc::new(AtomicBool::new(false));
     // Spawning a few threads to ensure that it will actually have an impact on the CPU usage.
@@ -168,6 +175,7 @@ fn test_consecutive_cpu_usage_update() {
         for pid in &pids {
             sys.refresh_processes_specifics(
                 ProcessesToUpdate::Some(&[*pid]),
+                true,
                 ProcessRefreshKind::new().with_cpu(),
             );
         }