show pools
Dump the status of internal memory pools. This is useful to track memory
usage when suspecting a memory leak for example. It does exactly the same
as the SIGQUIT when running in foreground except that it does not flush
the pools.
From time to time, some bugs are discovered that are caused by non-initialized
memory areas. It happens that most platforms return a zero-filled area upon
first malloc() thus hiding potential bugs. This patch also replaces malloc()
in pools with calloc() to ensure that all platforms exhibit the same behaviour
upon startup. In order to catch these bugs more easily, add a -dM command line
flag to enable memory poisonning. Optionally, passing -dM<byte> forces the
poisonning byte to <byte>.
A race condition exists in the hot reconfiguration code. It is
theorically possible that the second signal is sent during a free()
in the first list, which can cause crashes or freezes (the later
have been observed). Just set up a counter to ensure we do not
recurse.
New functions implemented:
- deinit_pollers: called at the end of deinit())
- prune_acl: called via list_for_each_entry_safe
Add missing pool_destroy2 calls:
- p->hdr_idx_pool
- pool2_tree64
Implement all task stopping:
- health-check: needs new "struct task" in the struct server
- queue processing: queue_mgt
- appsess_refresh: appsession_refresh
before (idle system):
==6079== LEAK SUMMARY:
==6079== definitely lost: 1,112 bytes in 75 blocks.
==6079== indirectly lost: 53,356 bytes in 2,090 blocks.
==6079== possibly lost: 52 bytes in 1 blocks.
==6079== still reachable: 150,996 bytes in 504 blocks.
==6079== suppressed: 0 bytes in 0 blocks.
after (idle system):
==6945== LEAK SUMMARY:
==6945== definitely lost: 7,644 bytes in 137 blocks.
==6945== indirectly lost: 9,913 bytes in 587 blocks.
==6945== possibly lost: 0 bytes in 0 blocks.
==6945== still reachable: 0 bytes in 0 blocks.
==6945== suppressed: 0 bytes in 0 blocks.
before (running system for ~2m):
==9343== LEAK SUMMARY:
==9343== definitely lost: 1,112 bytes in 75 blocks.
==9343== indirectly lost: 54,199 bytes in 2,122 blocks.
==9343== possibly lost: 52 bytes in 1 blocks.
==9343== still reachable: 151,128 bytes in 509 blocks.
==9343== suppressed: 0 bytes in 0 blocks.
after (running system for ~2m):
==11616== LEAK SUMMARY:
==11616== definitely lost: 7,644 bytes in 137 blocks.
==11616== indirectly lost: 9,981 bytes in 591 blocks.
==11616== possibly lost: 0 bytes in 0 blocks.
==11616== still reachable: 4 bytes in 1 blocks.
==11616== suppressed: 0 bytes in 0 blocks.
Still not perfect but significant improvement.
since pools v2, the way pools were destroyed at exit is incorrect
because it ought to account for users of those pools before freeing
them. This test also ensures there is no double free.
When we're interrupted by another instance, it is very likely
that the other one will need some memory. Now we know how to
free what is not used, so let's do it.
Also only free non-null pointers. Previously, pool_destroy()
did implicitly check for this case which was incidentely
needed.
- keep the number of users of each pool
- call the garbage collector on out of memory conditions
- sort the pools by size for faster creation
- force the alignment size to 16 bytes instead of 4*sizeof(void *)
