[nycphp-talk] Any apc experts out there?

Cliff Hirsch cliff at
Sun Mar 2 22:28:52 EST 2008

> On Sun, Mar 2, 2008 at 9:55 PM, Cliff Hirsch <cliff at> wrote:
>>  I just increased from 1 to 2 shm segments (30M each). But the apc memory
>> usage graph still indicates only 30M.
>>  Why isn't apc taking advantage of the 2nd shm?

>>Is APC using the first 30M to start with?  If it's not needed, perhaps it
>>won't allocate it, ie, the number of segments is the limit.

On 3/2/08 10:09 PM, "Austin Smith" <asmith at> wrote:

> I fought this battle awhile back building machine images for EC2
> servers. If memory serves, in the end I just had to boost the shm_size
> because shm_segments is deprecated (or just broken and
> soon-to-be-deprecated). I recall being a little annoyed at the
> discussions about this issue in bug trackers which mostly ended with
> someone sniping, "why would you want to use multiple segments?"
> Good luck,
> Austin

My apc memory usage is near 100%, so I assumed it would role into the 2nd
shm. Deprecated, eh. Well that explains things. Sure, increasing the
shm_size param would be trivial, but I thought max shm size was defined by
the OS and couldn't be set arbitrarily.

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