pthreadpool: Add a simple benchmark

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
pthreadpool: Avoid a malloc/free per job

pthreadpool_add_job is in our hottest code path for r/w intensive workloads, so
we should avoid anything CPU-intensive. pthreadpool used to malloc each job and
free it in the worker thread. This patch adds a FIFO queue for jobs that helper
threads copy from, avoiding constant malloc/free. This cuts user space
CPU in the local-bench-pthreadpool benchmark by roughly 10% on my system.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
pthreadpool: Allow multiple jobs to be received

This can avoid syscalls when multiple jobs are finished simultaneously

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
asys: Allow multiple results to be received

This makes use of C99 dynamic arrays. In this performance-sensitive code, I
would like to avoid malloc/free, and I think 15 years after the standard we
might be able to use this feature. Alternatively, we could use the "results"
memory area and store the jobids in the upper range, playing some cast-tricks.
Should work as well.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
smbd: Use asys_results

When multiple aio requests finish simultaneously, this saves a few syscalls

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Thu Mar 27 08:05:46 CET 2014 on sn-devel-104
ctdb-locking: Avoid memory leak

If lock_request could not be allocated, free lock_ctx since there can
only be a single lock_request per lock_ctx.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Martin Schwenke <martin@meltin.net>
ctdb-locking: Check for talloc_memdup error

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Martin Schwenke <martin@meltin.net>
ctdb-locking: Instead of comparing key, compare key hash

This replaces memory comparison of the key with integer comparison.
In addition, this also avoids scheduling locks with the same hash.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Martin Schwenke <martin@meltin.net>

Autobuild-User(master): Martin Schwenke <martins@samba.org>
Autobuild-Date(master): Fri Mar 28 05:28:58 CET 2014 on sn-devel-104