Hello,

We have a situation with a PHP script running as a cronjob, which is reported with 91M memory used.

I catched the pid with pmap and what i can observe the sum of the total memory reported is correct [ total 93320K ], but there is included a 64M usage:

b3f52000 65536K rw-s- [ shmid=0x15dd8001 ]

I repeated the process with 32M memory_limit in php.ini but the same 64M usage occurs:

(...)
089d7000 3452K rw--- [ anon ]
b3d3f000 772K rw--- [ anon ]
b3ec0000 4K rw--- [ anon ]
b3ec1000 65536K rw-s- [ shmid=0x15e30003 ]
b7f02000 44K rw--- [ anon ]
b7f15000 4K rw--- [ anon ]
bfd3c000 84K rwx-- [ stack ]
total 93312K

According to the pmap docs:
"shmid=n:
The mapping is a System V shared memory mapping. The shared memory identifier that the mapping was created with is reported."

Why would this peak of memory being generated?

Kernel: 2.6.18-92.1.10.el5PAE #1 SMP Tue Aug 5 08:14:05 EDT 2008 i686 i686 i386 GNU/Linux

cPanel 11.25.0-S45750 - WHM 11.25.0 - X 3.9
CENTOS 5.5 i686 standard on serverXX

Thank you,
Regards

Lehel