You are viewing a plain text version of this content. The canonical link for it is here.
Posted to users@httpd.apache.org by Honza Lefty Škoda <le...@multihost.cz> on 2010/11/21 12:55:45 UTC
[users@httpd] mod_fcgid ignoring both scores and process count
I am running performance benchmarks with ab2 on my server and I
discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
And if I make 15 concurrent requests fcgi starts 15 php processes at the
same time without worrying about FcgidSpawnScoreUpLimit!
I use mod_fcgid with suexec for php execution (via php-wrapper bash
script, which does a lot of magic including execs, chroot and setuid).
The configuration (for fcgid 2.3.6 on apache 2.2.15):
/etc/apache2/modules.d/20_mod_fcgid.conf:
25: FcgidMinProcessesPerClass 0
26: FcgidMaxProcessesPerClass 10
33: FcgidSpawnScore 10
34: FcgidTerminationScore 20
35: FcgidTimeScore 1
36: FcgidSpawnScoreUpLimit 25
By the way - according to documentation, FcgidMinProcessesPerClass in
VirtualHost section shouldn't work. For me, it does (and I'm happy with
it :)).
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Jeff Trawick <tr...@gmail.com>.
2010/11/22 Honza Lefty Škoda <le...@multihost.cz>:
> On 22.11.2010 02:55, Jeff Trawick wrote::
>> 2010/11/21 Jeff Trawick <tr...@gmail.com>:
>>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>>> On 21.11.2010 16:57, Jeff Trawick wrote::
>>>>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>>>>> I am running performance benchmarks with ab2 on my server and I
>>>>>> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
>>>>>> And if I make 15 concurrent requests fcgi starts 15 php processes at the
>>>>>> same time without worrying about FcgidSpawnScoreUpLimit!
>>>>>>
>>>>>> I use mod_fcgid with suexec for php execution (via php-wrapper bash
>>>>>> script, which does a lot of magic including execs, chroot and setuid).
>>>>>>
>>>>>> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>>>>>>
>>>>>> /etc/apache2/modules.d/20_mod_fcgid.conf:
>>>>>> 25: FcgidMinProcessesPerClass 0
>>>>>> 26: FcgidMaxProcessesPerClass 10
>>>>>>
>>>>>> 33: FcgidSpawnScore 10
>>>>>> 34: FcgidTerminationScore 20
>>>>>> 35: FcgidTimeScore 1
>>>>>> 36: FcgidSpawnScoreUpLimit 25
>>>>>
>>>>> I did find/fix one related issue this a.m.: the first process created
>>>>> didn't adjust the score, so you could in effect create one more
>>>>> process than desired during ramp-up. I didn't see your exact issue
>>>>> though.
>>>>>
>>>>> Two things:
>>>>>
>>>>> Does your "magic" wrapper logic preserve the pid created by mod_fcgid
>>>>> (i.e., use exec instead of fork)? If not, the fcgid PM will be
>>>>> confused and you're probably getting requests successfully processed
>>>>> between the time fcgid forks a child and when it exits. (That
>>>>> probably isn't a workable explanation since an exiting child would add
>>>>> a huge number -- 20 -- to the score. But please confirm anyway :) )
>>>> Yes, PID of php-cgi process matches the one in server-status worker list.
>>>>
>>>>>
>>>>> If you are preserving the pid (i.e., fcgid PM can track what it has
>>>>> created), turn on LogLevel info and see if you can get more insight
>>>>> into what is happening with spawn score manipulation/checking. Here's
>>>>> what I get using the directives you posted and hammering on one script
>>>>> with ab (>100 current clients):
>>>>
>>>> Good idea!
>>>> I tried to run the tests again with surprising results. Some
>>>> VirtualHosts break rules:
>>>>
>>>> Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11473) started
>>>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11474) started
>>>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11475) started
>>> ...
>>>>
>>>> After several benchmarks I found out that it's caused by the
>>>> FcgidMinProcessesPerClass which is set to 1 for some vhosts. When I set
>>>> this, scores are completely ignored!
>>>
>>> Thanks for finding that; I've now duplicated it. Hopefully it will be
>>> easy to resolve. (It acts like a classic merging bug, but the score
>>> configurations are supposed to be taken from the main vhost so merging
>>> is supposed to be irrelevant.)
>>>
>>
>> this fixes it for me:
>>
>> Index: modules/fcgid/fcgid_spawn_ctl.c
>> ===================================================================
>> --- modules/fcgid/fcgid_spawn_ctl.c (revision 1037483)
>> +++ modules/fcgid/fcgid_spawn_ctl.c (working copy)
>> @@ -178,7 +178,7 @@
>> if (current_node->inode == command->inode
>> && current_node->deviceid == command->deviceid
>> && !strcmp(current_node->cmdline, command->cmdline)
>> - && current_node->vhost_id == sconf->vhost_id
>> + && current_node->vhost_id == command->vhost_id
>> && current_node->uid == command->uid
>> && current_node->gid == command->gid)
>> break;
>>
>
> Works great!
thanks for reporting back
> Now I am facing another score related issue - on gracefull
> reload, the scores are kept, but the processes are killed (which results
> in really high scores). After that, no fcgi processes are spawned for
> quite a long time. It would be wise to reset scores. And as I don't know
> any other (more official) way to submit bugs, I write it here again. :)
http://issues.apache.org/bugzilla/
product = Apache httpd-2
component = mod_fcgid
(it is helpful to search for existing bugs in the component before
opening a potential duplicate)
there are a couple of existing bugs on graceful restart weirdness
https://issues.apache.org/bugzilla/show_bug.cgi?id=48769
https://issues.apache.org/bugzilla/show_bug.cgi?id=48949
you might want to add your observation to the latter of these two
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Honza Lefty Škoda <le...@multihost.cz>.
On 22.11.2010 02:55, Jeff Trawick wrote::
> 2010/11/21 Jeff Trawick <tr...@gmail.com>:
>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>> On 21.11.2010 16:57, Jeff Trawick wrote::
>>>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>>>> I am running performance benchmarks with ab2 on my server and I
>>>>> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
>>>>> And if I make 15 concurrent requests fcgi starts 15 php processes at the
>>>>> same time without worrying about FcgidSpawnScoreUpLimit!
>>>>>
>>>>> I use mod_fcgid with suexec for php execution (via php-wrapper bash
>>>>> script, which does a lot of magic including execs, chroot and setuid).
>>>>>
>>>>> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>>>>>
>>>>> /etc/apache2/modules.d/20_mod_fcgid.conf:
>>>>> 25: FcgidMinProcessesPerClass 0
>>>>> 26: FcgidMaxProcessesPerClass 10
>>>>>
>>>>> 33: FcgidSpawnScore 10
>>>>> 34: FcgidTerminationScore 20
>>>>> 35: FcgidTimeScore 1
>>>>> 36: FcgidSpawnScoreUpLimit 25
>>>>
>>>> I did find/fix one related issue this a.m.: the first process created
>>>> didn't adjust the score, so you could in effect create one more
>>>> process than desired during ramp-up. I didn't see your exact issue
>>>> though.
>>>>
>>>> Two things:
>>>>
>>>> Does your "magic" wrapper logic preserve the pid created by mod_fcgid
>>>> (i.e., use exec instead of fork)? If not, the fcgid PM will be
>>>> confused and you're probably getting requests successfully processed
>>>> between the time fcgid forks a child and when it exits. (That
>>>> probably isn't a workable explanation since an exiting child would add
>>>> a huge number -- 20 -- to the score. But please confirm anyway :) )
>>> Yes, PID of php-cgi process matches the one in server-status worker list.
>>>
>>>>
>>>> If you are preserving the pid (i.e., fcgid PM can track what it has
>>>> created), turn on LogLevel info and see if you can get more insight
>>>> into what is happening with spawn score manipulation/checking. Here's
>>>> what I get using the directives you posted and hammering on one script
>>>> with ab (>100 current clients):
>>>
>>> Good idea!
>>> I tried to run the tests again with surprising results. Some
>>> VirtualHosts break rules:
>>>
>>> Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11473) started
>>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11474) started
>>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>>> *:/opt/hostik/webbin/php-wrapper.fcgi(11475) started
>> ...
>>>
>>> After several benchmarks I found out that it's caused by the
>>> FcgidMinProcessesPerClass which is set to 1 for some vhosts. When I set
>>> this, scores are completely ignored!
>>
>> Thanks for finding that; I've now duplicated it. Hopefully it will be
>> easy to resolve. (It acts like a classic merging bug, but the score
>> configurations are supposed to be taken from the main vhost so merging
>> is supposed to be irrelevant.)
>>
>
> this fixes it for me:
>
> Index: modules/fcgid/fcgid_spawn_ctl.c
> ===================================================================
> --- modules/fcgid/fcgid_spawn_ctl.c (revision 1037483)
> +++ modules/fcgid/fcgid_spawn_ctl.c (working copy)
> @@ -178,7 +178,7 @@
> if (current_node->inode == command->inode
> && current_node->deviceid == command->deviceid
> && !strcmp(current_node->cmdline, command->cmdline)
> - && current_node->vhost_id == sconf->vhost_id
> + && current_node->vhost_id == command->vhost_id
> && current_node->uid == command->uid
> && current_node->gid == command->gid)
> break;
>
Works great! Now I am facing another score related issue - on gracefull
reload, the scores are kept, but the processes are killed (which results
in really high scores). After that, no fcgi processes are spawned for
quite a long time. It would be wise to reset scores. And as I don't know
any other (more official) way to submit bugs, I write it here again. :)
> ---------------------------------------------------------------------
> The official User-To-User support forum of the Apache HTTP Server Project.
> See <URL:http://httpd.apache.org/userslist.html> for more info.
> To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
> " from the digest: users-digest-unsubscribe@httpd.apache.org
> For additional commands, e-mail: users-help@httpd.apache.org
>
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Jeff Trawick <tr...@gmail.com>.
2010/11/21 Jeff Trawick <tr...@gmail.com>:
> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>
>>
>> On 21.11.2010 16:57, Jeff Trawick wrote::
>>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>>> I am running performance benchmarks with ab2 on my server and I
>>>> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
>>>> And if I make 15 concurrent requests fcgi starts 15 php processes at the
>>>> same time without worrying about FcgidSpawnScoreUpLimit!
>>>>
>>>> I use mod_fcgid with suexec for php execution (via php-wrapper bash
>>>> script, which does a lot of magic including execs, chroot and setuid).
>>>>
>>>> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>>>>
>>>> /etc/apache2/modules.d/20_mod_fcgid.conf:
>>>> 25: FcgidMinProcessesPerClass 0
>>>> 26: FcgidMaxProcessesPerClass 10
>>>>
>>>> 33: FcgidSpawnScore 10
>>>> 34: FcgidTerminationScore 20
>>>> 35: FcgidTimeScore 1
>>>> 36: FcgidSpawnScoreUpLimit 25
>>>
>>> I did find/fix one related issue this a.m.: the first process created
>>> didn't adjust the score, so you could in effect create one more
>>> process than desired during ramp-up. I didn't see your exact issue
>>> though.
>>>
>>> Two things:
>>>
>>> Does your "magic" wrapper logic preserve the pid created by mod_fcgid
>>> (i.e., use exec instead of fork)? If not, the fcgid PM will be
>>> confused and you're probably getting requests successfully processed
>>> between the time fcgid forks a child and when it exits. (That
>>> probably isn't a workable explanation since an exiting child would add
>>> a huge number -- 20 -- to the score. But please confirm anyway :) )
>> Yes, PID of php-cgi process matches the one in server-status worker list.
>>
>>>
>>> If you are preserving the pid (i.e., fcgid PM can track what it has
>>> created), turn on LogLevel info and see if you can get more insight
>>> into what is happening with spawn score manipulation/checking. Here's
>>> what I get using the directives you posted and hammering on one script
>>> with ab (>100 current clients):
>>
>> Good idea!
>> I tried to run the tests again with surprising results. Some
>> VirtualHosts break rules:
>>
>> Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>> *:/opt/hostik/webbin/php-wrapper.fcgi(11473) started
>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>> *:/opt/hostik/webbin/php-wrapper.fcgi(11474) started
>> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
>> *:/opt/hostik/webbin/php-wrapper.fcgi(11475) started
> ...
>>
>> After several benchmarks I found out that it's caused by the
>> FcgidMinProcessesPerClass which is set to 1 for some vhosts. When I set
>> this, scores are completely ignored!
>
> Thanks for finding that; I've now duplicated it. Hopefully it will be
> easy to resolve. (It acts like a classic merging bug, but the score
> configurations are supposed to be taken from the main vhost so merging
> is supposed to be irrelevant.)
>
this fixes it for me:
Index: modules/fcgid/fcgid_spawn_ctl.c
===================================================================
--- modules/fcgid/fcgid_spawn_ctl.c (revision 1037483)
+++ modules/fcgid/fcgid_spawn_ctl.c (working copy)
@@ -178,7 +178,7 @@
if (current_node->inode == command->inode
&& current_node->deviceid == command->deviceid
&& !strcmp(current_node->cmdline, command->cmdline)
- && current_node->vhost_id == sconf->vhost_id
+ && current_node->vhost_id == command->vhost_id
&& current_node->uid == command->uid
&& current_node->gid == command->gid)
break;
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Jeff Trawick <tr...@gmail.com>.
2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>
>
> On 21.11.2010 16:57, Jeff Trawick wrote::
>> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>>> I am running performance benchmarks with ab2 on my server and I
>>> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
>>> And if I make 15 concurrent requests fcgi starts 15 php processes at the
>>> same time without worrying about FcgidSpawnScoreUpLimit!
>>>
>>> I use mod_fcgid with suexec for php execution (via php-wrapper bash
>>> script, which does a lot of magic including execs, chroot and setuid).
>>>
>>> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>>>
>>> /etc/apache2/modules.d/20_mod_fcgid.conf:
>>> 25: FcgidMinProcessesPerClass 0
>>> 26: FcgidMaxProcessesPerClass 10
>>>
>>> 33: FcgidSpawnScore 10
>>> 34: FcgidTerminationScore 20
>>> 35: FcgidTimeScore 1
>>> 36: FcgidSpawnScoreUpLimit 25
>>
>> I did find/fix one related issue this a.m.: the first process created
>> didn't adjust the score, so you could in effect create one more
>> process than desired during ramp-up. I didn't see your exact issue
>> though.
>>
>> Two things:
>>
>> Does your "magic" wrapper logic preserve the pid created by mod_fcgid
>> (i.e., use exec instead of fork)? If not, the fcgid PM will be
>> confused and you're probably getting requests successfully processed
>> between the time fcgid forks a child and when it exits. (That
>> probably isn't a workable explanation since an exiting child would add
>> a huge number -- 20 -- to the score. But please confirm anyway :) )
> Yes, PID of php-cgi process matches the one in server-status worker list.
>
>>
>> If you are preserving the pid (i.e., fcgid PM can track what it has
>> created), turn on LogLevel info and see if you can get more insight
>> into what is happening with spawn score manipulation/checking. Here's
>> what I get using the directives you posted and hammering on one script
>> with ab (>100 current clients):
>
> Good idea!
> I tried to run the tests again with surprising results. Some
> VirtualHosts break rules:
>
> Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
> *:/opt/hostik/webbin/php-wrapper.fcgi(11473) started
> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
> *:/opt/hostik/webbin/php-wrapper.fcgi(11474) started
> [Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
> *:/opt/hostik/webbin/php-wrapper.fcgi(11475) started
...
>
> After several benchmarks I found out that it's caused by the
> FcgidMinProcessesPerClass which is set to 1 for some vhosts. When I set
> this, scores are completely ignored!
Thanks for finding that; I've now duplicated it. Hopefully it will be
easy to resolve. (It acts like a classic merging bug, but the score
configurations are supposed to be taken from the main vhost so merging
is supposed to be irrelevant.)
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Honza Lefty Škoda <le...@multihost.cz>.
On 21.11.2010 16:57, Jeff Trawick wrote::
> 2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
>> I am running performance benchmarks with ab2 on my server and I
>> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
>> And if I make 15 concurrent requests fcgi starts 15 php processes at the
>> same time without worrying about FcgidSpawnScoreUpLimit!
>>
>> I use mod_fcgid with suexec for php execution (via php-wrapper bash
>> script, which does a lot of magic including execs, chroot and setuid).
>>
>> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>>
>> /etc/apache2/modules.d/20_mod_fcgid.conf:
>> 25: FcgidMinProcessesPerClass 0
>> 26: FcgidMaxProcessesPerClass 10
>>
>> 33: FcgidSpawnScore 10
>> 34: FcgidTerminationScore 20
>> 35: FcgidTimeScore 1
>> 36: FcgidSpawnScoreUpLimit 25
>
> I did find/fix one related issue this a.m.: the first process created
> didn't adjust the score, so you could in effect create one more
> process than desired during ramp-up. I didn't see your exact issue
> though.
>
> Two things:
>
> Does your "magic" wrapper logic preserve the pid created by mod_fcgid
> (i.e., use exec instead of fork)? If not, the fcgid PM will be
> confused and you're probably getting requests successfully processed
> between the time fcgid forks a child and when it exits. (That
> probably isn't a workable explanation since an exiting child would add
> a huge number -- 20 -- to the score. But please confirm anyway :) )
Yes, PID of php-cgi process matches the one in server-status worker list.
>
> If you are preserving the pid (i.e., fcgid PM can track what it has
> created), turn on LogLevel info and see if you can get more insight
> into what is happening with spawn score manipulation/checking. Here's
> what I get using the directives you posted and hammering on one script
> with ab (>100 current clients):
Good idea!
I tried to run the tests again with surprising results. Some
VirtualHosts break rules:
Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11473) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11474) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11475) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11476) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11477) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11479) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11481) started
[Sun Nov 21 16:57:33 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(11482) started
and some does not:
[Sun Nov 21 17:08:10 2010] [info] mod_fcgid: server
*:/opt/hostik/webbin/php-wrapper.fcgi(15109) started
[Sun Nov 21 17:08:11 2010] [info] mod_fcgid:
/opt/hostik/webbin/php-wrapper.fcgi spawn score 39 >= 25, skip the spawn
request
[Sun Nov 21 17:08:12 2010] [info] mod_fcgid:
/opt/hostik/webbin/php-wrapper.fcgi spawn score 38 >= 25, skip the spawn
request
After several benchmarks I found out that it's caused by the
FcgidMinProcessesPerClass which is set to 1 for some vhosts. When I set
this, scores are completely ignored!
>> By the way - according to documentation, FcgidMinProcessesPerClass in
>> VirtualHost section shouldn't work. For me, it does (and I'm happy with
>> it :)).
>
> Is this where you are looking?
> http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidminprocessesperclass
>
> If so, can you explain further what you mean, as I don't see any
> indication that it shouldn't work.
Sorry, I have probably read some older version. Now it makes sense :)
>
> ---------------------------------------------------------------------
> The official User-To-User support forum of the Apache HTTP Server Project.
> See <URL:http://httpd.apache.org/userslist.html> for more info.
> To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
> " from the digest: users-digest-unsubscribe@httpd.apache.org
> For additional commands, e-mail: users-help@httpd.apache.org
>
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org
Re: [users@httpd] mod_fcgid ignoring both scores and process count
Posted by Jeff Trawick <tr...@gmail.com>.
2010/11/21 Honza Lefty Škoda <le...@multihost.cz>:
> I am running performance benchmarks with ab2 on my server and I
> discovered that fcgid creates much more than FcgidMaxProcessesPerClass.
> And if I make 15 concurrent requests fcgi starts 15 php processes at the
> same time without worrying about FcgidSpawnScoreUpLimit!
>
> I use mod_fcgid with suexec for php execution (via php-wrapper bash
> script, which does a lot of magic including execs, chroot and setuid).
>
> The configuration (for fcgid 2.3.6 on apache 2.2.15):
>
> /etc/apache2/modules.d/20_mod_fcgid.conf:
> 25: FcgidMinProcessesPerClass 0
> 26: FcgidMaxProcessesPerClass 10
>
> 33: FcgidSpawnScore 10
> 34: FcgidTerminationScore 20
> 35: FcgidTimeScore 1
> 36: FcgidSpawnScoreUpLimit 25
I did find/fix one related issue this a.m.: the first process created
didn't adjust the score, so you could in effect create one more
process than desired during ramp-up. I didn't see your exact issue
though.
Two things:
Does your "magic" wrapper logic preserve the pid created by mod_fcgid
(i.e., use exec instead of fork)? If not, the fcgid PM will be
confused and you're probably getting requests successfully processed
between the time fcgid forks a child and when it exits. (That
probably isn't a workable explanation since an exiting child would add
a huge number -- 20 -- to the score. But please confirm anyway :) )
If you are preserving the pid (i.e., fcgid PM can track what it has
created), turn on LogLevel info and see if you can get more insight
into what is happening with spawn score manipulation/checking. Here's
what I get using the directives you posted and hammering on one script
with ab (>100 current clients):
[Sun Nov 21 10:17:53 2010] [info] Server built: Nov 11 2010 13:37:51
[Sun Nov 21 10:17:53 2010] [debug] prefork.c(1018): AcceptMutex:
sysvsem (default: sysvsem)
[Sun Nov 21 10:18:03 2010] [info] mod_fcgid: server
127.0.1.1:/home/trawick/myhg/apache/fcgid/apps/info.pl(10258) started
[Sun Nov 21 10:18:04 2010] [info] mod_fcgid: server
127.0.1.1:/home/trawick/myhg/apache/fcgid/apps/info.pl(10260) started
[Sun Nov 21 10:18:04 2010] [info] mod_fcgid: server
127.0.1.1:/home/trawick/myhg/apache/fcgid/apps/info.pl(10261) started
[Sun Nov 21 10:18:04 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 29 >= 25,
skip the spawn request
[Sun Nov 21 10:18:06 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 27 >= 25,
skip the spawn request
[Sun Nov 21 10:18:06 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 27 >= 25,
skip the spawn request
[Sun Nov 21 10:18:06 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 27 >= 25,
skip the spawn request
[Sun Nov 21 10:18:07 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 26 >= 25,
skip the spawn request
[Sun Nov 21 10:18:07 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 26 >= 25,
skip the spawn request
[Sun Nov 21 10:18:07 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 26 >= 25,
skip the spawn request
[Sun Nov 21 10:18:07 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 26 >= 25,
skip the spawn request
[Sun Nov 21 10:18:07 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 26 >= 25,
skip the spawn request
[Sun Nov 21 10:18:08 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 25 >= 25,
skip the spawn request
[Sun Nov 21 10:18:08 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 25 >= 25,
skip the spawn request
[Sun Nov 21 10:18:08 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 25 >= 25,
skip the spawn request
[Sun Nov 21 10:18:08 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 25 >= 25,
skip the spawn request
[Sun Nov 21 10:18:09 2010] [info] mod_fcgid: server
127.0.1.1:/home/trawick/myhg/apache/fcgid/apps/info.pl(10356) started
[Sun Nov 21 10:18:09 2010] [info] mod_fcgid:
/home/trawick/myhg/apache/fcgid/apps/info.pl spawn score 34 >= 25,
skip the spawn request
That looks good to me.
> By the way - according to documentation, FcgidMinProcessesPerClass in
> VirtualHost section shouldn't work. For me, it does (and I'm happy with
> it :)).
Is this where you are looking?
http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidminprocessesperclass
If so, can you explain further what you mean, as I don't see any
indication that it shouldn't work.
---------------------------------------------------------------------
The official User-To-User support forum of the Apache HTTP Server Project.
See <URL:http://httpd.apache.org/userslist.html> for more info.
To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
" from the digest: users-digest-unsubscribe@httpd.apache.org
For additional commands, e-mail: users-help@httpd.apache.org