[Galaxy Y GT-S5360 Android Development] kurotsugi:
nice explanation and review. I still don't understand why people are still asking for more free ram. basicly your device is OK as long as the ram usage doesn't hit 250. check this out.

1. average ram usage for heavy app is 30-40 mb. even my heavy PSX emulator only hit 30mb. as long as you have ~30 mb free space you won't get a trouble running an heavy app.

2. ram write consumes more battery power.

3. android has 'smart' ram management. it has at least 4 slot for apps. system services, cached app, background app, running app. your app is cached to minimilize ram write. more free ram space means less space for cached app and consequently more ram write. your device will use more battery power than usual.

4. speed increase in tweak is not determined by the ram free space. it determined how we treat the app running in our device. in my tweak it is done by this part

echo "64000" > /proc/sys/kernel/msgmni;
echo "64000" > /proc/sys/kernel/msgmax;
echo "20000000" > /proc/sys/kernel/sched_latency_ns;
echo "2500000" > /proc/sys/kernel/sched_wakeup_granularity_ns;
echo "1000000" > /proc/sys/kernel/sched_min_granularity_ns;
echo "500 512000 64 2048" > /proc/sys/kernel/sem;
echo "268435456" > /proc/sys/kernel/shmmax;
echo "2097152" > /proc/sys/kernel/shmall;
echo "30" > /proc/sys/kernel/panic;
echo "0" > /proc/sys/kernel/panic_on_oops;
echo "5000" > /proc/sys/kernel/threads-max;
echo "10" > /proc/sys/fs/lease-break-time;
echo "65536" > /proc/sys/fs/file-max;
echo "60" > /proc/sys/kernel/panic;
echo "0" > /proc/sys/kernel/panic_on_oops;
echo "1" > /proc/sys/kernel/sched_compat_yield;
echo "256000" > /proc/sys/kernel/sched_shares_ratelimit;
echo "0" > /proc/sys/kernel/ctrl-alt-del;
echo "kernel kick-----------[OK]" | tee -a $LOG_FILE;

# OOM
echo "0" > /proc/sys/vm/laptop_mode;
echo "30" > /proc/sys/vm/swappiness;
echo "2000" > /proc/sys/vm/dirty_writeback_centisecs;
echo "1000" > /proc/sys/vm/dirty_expire_centisecs;
echo "15" > /proc/sys/vm/dirty_ratio;
echo "100 100" > /proc/sys/vm/lowmem_reserve_ratio;
echo "1" > /proc/sys/vm/highmem_is_dirtyable;
echo "4" > /proc/sys/vm/min_free_order_shift;
echo "0" > /proc/sys/vm/oom_kill_allocating_task;
echo "0" > /proc/sys/vm/panic_on_oom;
echo "70" > /proc/sys/vm/overcommit_ratio;
echo "3" > /proc/sys/vm/page-cluster;
echo "3" > /proc/sys/vm/drop_caches;
echo "16384" > /proc/sys/vm/min_free_kbytes;
echo "50" > /proc/sys/vm/vfs_cache_pressure;
echo "70" > /proc/sys/vm/dirty_background_ratio;
echo "0" > /proc/sys/vm/block_dump;
echo "0" > /sys/module/lowmemorykiller/parameters/debug_level;
echo "64" > /sys/module/lowmemorykiller/parameters/cost;
echo "0,4,6,8,14,15" > /sys/module/lowmemorykiller/parameters/adj;

while the setting for the ram space is only this one

echo "1536,2048,4096,15360,17920,20480" > /sys/module/lowmemorykiller/parameters/minfree;

now you can see how insignificant ram free space tweak to increase your devices performace (lol).

now check into last three number in that part. its 15360,17920,20480 the standard value is 15360,15360,15360 this number determines the app slot for cached app, backgroud-running app, and free ram space. the system will read it as 60,70,80, mb or 60,60,60. the reason why my tweak is more battery friendly is because I have more space for cached, and background app which will reduce the ram write frequency and consequently --more battery saving--.