memory_limit default View as Markdown

On Mon, Jun 16, 2014 at 1:50 PM, Pascal Chevrel pascal.chevrel@free.fr
wrote:

Hi internals people,

I was curious to know why the memory limit in php.ini was set to 128MB so
I digged into the repository history and I saw that it was bumped from 16MB
to that value in 2006: https://github.com/php/php-src/commit/
3ffc1c8f4a1e4c1658f94038e009e226258a65a4#diff-
299b21e0851494929e62b81e8d91b5b3

Since there is no reference to a bug in the commit and I couldn't find
anything about it on the net, I thought I would ask at the source in
internals.

Was it changed because the defaut value was too low for PHP to work
correctly? Or was the change done to reflect the state of hosting solutions
back then? I am curious to know why 128 and not 64 or 256 actually. If this
is the result of an analysis of the state of hosting, I am also wondering
if 8 years later php.ini settings that depend on hardware like memory are
still the right defaults.

Thanks for your hindsight on this!

Pascal

--

adding Dmitry to the thread.

--
Ferenc Kovács
@Tyr43l - http://tyrael.hu

Hi internals people,

I was curious to know why the memory limit in php.ini was set to 128MB so
I digged into the repository history and I saw that it was bumped from 16MB
to that value in 2006: https://github.com/php/php-src/commit/
3ffc1c8f4a1e4c1658f94038e009e226258a65a4#diff-
299b21e0851494929e62b81e8d91b5b3

Since there is no reference to a bug in the commit and I couldn't find
anything about it on the net, I thought I would ask at the source in
internals.

Was it changed because the defaut value was too low for PHP to work
correctly? Or was the change done to reflect the state of hosting solutions
back then? I am curious to know why 128 and not 64 or 256 actually. If this
is the result of an analysis of the state of hosting, I am also wondering
if 8 years later php.ini settings that depend on hardware like memory are
still the right defaults.

See a (public) discussion from 2006 at
http://php.markmail.org/thread/kw7yzcr37j4xi7ab

Thanks for your hindsight on this!

Pascal

hi Pascal,

There are few reasons:

• PHP applications became more fat. (near everyone now uses some framework)
• PHP was optimized to use more memory from controlled memory area instead
  of system heap
• PHP introduced different caches that takes memory in cost of better
  performance
• Some new features increased the size of some basic structures (e.g.
  zend_class_entry) and it made PHP consume more memory
• RAM became much chipper

We did some analyzes that time, but I can't remember what exactly.

In any case, if you speak about shared hosting, you should configure PHP
careful and change the default settings according to amount of available
RAM, expected number of PHP processes and expected average memory
consumption.

Thanks. Dmitry.

On Mon, Jun 16, 2014 at 3:50 PM, Pascal Chevrel pascal.chevrel@free.fr
wrote:

Hi internals people,

I was curious to know why the memory limit in php.ini was set to 128MB so
I digged into the repository history and I saw that it was bumped from 16MB
to that value in 2006: https://github.com/php/php-src/commit/
3ffc1c8f4a1e4c1658f94038e009e226258a65a4#diff-
299b21e0851494929e62b81e8d91b5b3

Since there is no reference to a bug in the commit and I couldn't find
anything about it on the net, I thought I would ask at the source in
internals.

Was it changed because the defaut value was too low for PHP to work
correctly? Or was the change done to reflect the state of hosting solutions
back then? I am curious to know why 128 and not 64 or 256 actually. If this
is the result of an analysis of the state of hosting, I am also wondering
if 8 years later php.ini settings that depend on hardware like memory are
still the right defaults.

Thanks for your hindsight on this!

Pascal