Edit report at https://bugs.php.net/bug.php?id=65338&edit=1
ID: 65338
Updated by: a...@php.net
Reported by: erics...@php.net
Summary: Enabling both php_opcache and php_wincache AVs on
shutdown
Status: Feedback
Type: Bug
Package: Reproducible crash
Operating System: Windows
PHP Version: 5.5.1
Assigned To: dmitry
Block user comment: N
Private report: N
New Comment:
@Eric ok, so the catch is to use the wincache with disabled opcode cache.
Whereby
interned strings are neither opcode cache nor any other functionality. The
patch
would solve it only for newer PHP versions, maybe it should be possible to
disable
interned strings explicitly in wincache/opcache, maybe per ini? That would
solve
it also for users with older PHP without TS.
@Jan that's obvious now where people start to mix the cache engines :)
Previous Comments:
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[2013-07-27 05:02:11] paj...@php.net
Agreed,should be applied in php-src and
github repos.
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[2013-07-27 01:27:59] phpdev at ehrhardt dot nl
The problem is so obvious, that I am surprised it did not com to surface
earlier. And the patch is elegant: do not assume interned_strings_start
is still the same, but free only the memory that you owned at startup.
In fact, the patch should be backported to PHP 5.4 as well. I do not
have a use case for X86, but I ran into the same problem woth PHP 5.4
X64. I know this is no official version, but as an illustration of the
problem it still is useful.
Compare these two builds:
https://dl.dropboxusercontent.com/u/8954372/php-5.4.17-nts-Win32-VC9-x64.zip
https://dl.dropboxusercontent.com/u/8954372/php-5.4.17-nts-Win32-VC9-x64_patched.zip
Try the unpatched one first. Put this in your php.ini:
extension=php_wincache.dll
zend_extension=ext/php_opcache.dll
zend_opcache.memory_consumption=128
zend_opcache.interned_strings_buffer=8
zend_opcache.max_accelerated_files=4000
zend_opcache.revalidate_freq=60
zend_opcache.fast_shutdown=1
zend_opcache.enable_cli=1
wincache.ocenabled=0
wincache.fcenabled=0
wincache.ucachesize=768
wincache.enablecli=1
session.savehandler=wincache
Then run from the commandline in your php-directory:
php-cgi.exe -m
php-cgi will crash after showing the loaded modules. Debugging with VC9
gave this result: http://x32.elijst.nl/zendfree.png
Quite another breakpoint as in the PHP 5.5 example, but with the same
cause: freeing memory you do not own.
In the patched build I backported Eric's patch for zend_string.c to PHP
5.4. Result: no crash anymore.
A last remark: i do not think the problem is Windows specific. This is
exectly the same problem, but with the combination of opcache and apc:
http://svn.php.net/viewvc?view=revision&revision=330859
------------------------------------------------------------------------
[2013-07-26 21:07:09] me at laurinkeithdavis dot com
I can confirm that this patch works as well.
https://bugs.php.net/bug.php?id=65247
------------------------------------------------------------------------
[2013-07-26 16:48:39] phpdev at ehrhardt dot nl
@Anatol: Xinchen ran into the same problem while combining APC usercache with
OPcache opcode cache. See
http://svn.php.net/viewvc?view=revision&revision=330859
He solved it by disabling interned_string.
@Eric: I can confirm your patch works. Tested it as well under X86 as X64.
------------------------------------------------------------------------
[2013-07-26 16:04:36] erics...@php.net
a...@php.net said
> What is the catch/sense of using both at the same time?
Wincache provides a file cache, session cache, user property cache as well as
an opcode cache. Further, it's possible to disable the opcode cache.
On PHP5.5, we (Wincache support folks) expect customers to enable the Zend
opcache (because it's in 'core', and probably does more optimizing than
Wincache does), but continue to use Wincache for file, session and user cache.
------------------------------------------------------------------------
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