Weird problem. The DB repeatedly waits for 1 second.

[Nicolás Lichtmaier <jn...@synapsis-sa.com.ar>]

I'm having a very weird problem. The db is veeery slow. I cannot finish 
a checkout operation successfuly. I've ran strace to the apache process 
and I saw lots of:


select(0, NULL, NULL, NULL, {1, 0})     = 0 (Timeout)
pread(16, "\274\1\0\0U\215\f\0\271\3\0\0\254\3\0\0b\2\0\0\214\0(\3"..., 
4096, 3903488) = 4096
select(0, NULL, NULL, NULL, {1, 0})     = 0 (Timeout)
pread(16, "\\\1\0\0\f\267\v\0%\3\0\0\26\3\0\0004\3\0\0P\0\204\10\1"..., 
4096, 3297280) = 4096
select(0, NULL, NULL, NULL, {1, 0})     = 0 (Timeout)
pread(16, "]\1\0\0\235\277\2\0-\3\0\0\36\3\0\0008\3\0\0J\0\200\10"..., 
4096, 3330048) = 4096

I've used gdb and I've found out that the problem is inside Berkeley DB. 
When trying to get some data from the DB, it calls __memp_alloc to get 
some cache space (according what I've read). This functions calls 
os_sleep(1) several times. There are comments in Berkeley DB source code 
explaining that such condition is seen when there's no memory, but I 
have plenty of memory here (2 Gb of RAM).

I'm attaching the a full stack trace.

Thanks for any advice you can give me.


-- 
Nicolás Lichtmaier.-
Synapsis Argentina
+54(11)4314-3000 (int. 231)