Activating Turck MMCache after installation - MediaWiki-l

Carlton B

20 Jun 20 Jun

8:55 a.m.

New subject: [Mediawiki-l] Activating Turck MMCache after installation

-----Original Message----- From: mediawiki-l-bounces(a)Wikimedia.org [mailto:mediawiki-l-bounces@Wikimedia.org]On Behalf Of David Liontooth Sent: Monday, June 20, 2005 5:44 PM To: mediawiki-l(a)Wikimedia.org Subject: [Mediawiki-l] Activating Turck MMCache after installation When I set up my first MediaWiki (nice work, btw!), I got "Turck MMCache not installed", even though I had just installed it. (I assume some app or daemon needed to be reloaded to detect it -- which one?) Later, when I installed a second wiki, Turck MMCache was detected, and I activated it. Seeing the result of the activation in LocalSettings.php, I uncommented the same line for the other wiki -- $wgUseTurckShm = function_exists( 'mmcache_get' ) && php_sapi_name() == 'apache'; The effect was a messed up cache function -- the second wiki's Main_Page would consistently display in the first wiki. If I selected [Edit] and Preview, I would see the first wiki's real Main_Page intact, but saving it would revert the display to the second wiki's front page. Nikerabbit on #mediawiki irc diagnosed it and I fixed the problem easily -- whew. But how do I properly activate Turck MMCache for a wiki that is already installed?

This does not answer your question at all, but I experienced some frustrating problems using Turck MMCache and I advise not using it if you're having problems with it. The answer I received here, if I understood it correctly, suggest that MediaWiki has never been able to satisfactory integrate the data caching feature of Turck in a stable or satisfactory way, causing different people to have different problems with it. Thus, you shouldn't enable this option in LocalSettings.php. You might be concerned about losing cache capability, but (as I understand) even if you disable the option, you still get the benefit of Turck caching compiled php scripts, which is a big benefit.

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Carlton B

11:54 a.m.

New subject: [Mediawiki-l] Activating Turck MMCache after installation

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-----Original Message----- From: mediawiki-l-bounces(a)Wikimedia.org [mailto:mediawiki-l-bounces@Wikimedia.org]On Behalf Of David Liontooth Sent: Monday, June 20, 2005 8:13 PM To: MediaWiki announcements and site admin list Subject: Re: [Mediawiki-l] Activating Turck MMCache after installation Carlton B wrote:

(as I understand) even if you disable the option, you still get the benefit of Turck caching compiled php scripts, which is a big benefit.

Really? As long as Turck caching is installed, mediawiki benefits even if this line is commented out? $wgUseTurckShm = function_exists( 'mmcache_get' ) && php_sapi_name() > == 'apache';

Yes, if I've understood correctly Brion's response to my problem. In that message, which was sent to the list, he said:

...

Turck does an excellent job of caching compiled PHP code (this requires NO configuration in LocalSettings.php, as it's completely independent of our code), but it's less clear that trying to shove other data in it helps, and it's not well tested or used by us.

Thus, I disabled Turck by commenting the line that sets $wgUseTurckShm. It fixed my problems. Since my site is still small and I am not benchmarking, I wouldn't know if it helped or hurt performance at this point.

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David Liontooth

7:13 p.m.

New subject: [Mediawiki-l] Activating Turck MMCache after installation

MHart wrote:

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I enable mmcache on all sites - I have about 5 running on one server, all with mmcache enabled, without any problems. I did not, however, attempt to go back to sites that were previously setup and get them running with mmcache, rather I re-setup the scripts in a different folder and updated the server settings. - MHart

Are you using a separate database for each wiki? If you are, you shouldn't be running into the problem I ran into (if I understand Carlton right). If you're using the same database, that would be interesting. Dave

...

----- Original Message ----- From: "Carlton B" <carltonb(a)mindspring.com> To: "MediaWiki announcements and site admin list" <mediawiki-l(a)Wikimedia.org> Sent: Monday, June 20, 2005 4:55 AM Subject: RE: [Mediawiki-l] Activating Turck MMCache after installation

-----Original Message----- From: mediawiki-l-bounces(a)Wikimedia.org [mailto:mediawiki-l-bounces@Wikimedia.org]On Behalf Of David Liontooth Sent: Monday, June 20, 2005 5:44 PM To: mediawiki-l(a)Wikimedia.org Subject: [Mediawiki-l] Activating Turck MMCache after installation When I set up my first MediaWiki (nice work, btw!), I got "Turck MMCache not installed", even though I had just installed it. (I assume some app or daemon needed to be reloaded to detect it -- which one?) Later, when I installed a second wiki, Turck MMCache was detected, and I activated it. Seeing the result of the activation in LocalSettings.php, I uncommented the same line for the other wiki -- $wgUseTurckShm = function_exists( 'mmcache_get' ) && php_sapi_name() == 'apache'; The effect was a messed up cache function -- the second wiki's Main_Page would consistently display in the first wiki. If I selected [Edit] and Preview, I would see the first wiki's real Main_Page intact, but saving it would revert the display to the second wiki's front page. Nikerabbit on #mediawiki irc diagnosed it and I fixed the problem easily -- whew. But how do I properly activate Turck MMCache for a wiki that is already installed?

This does not answer your question at all, but I experienced some frustrating problems using Turck MMCache and I advise not using it if you're having problems with it. The answer I received here, if I understood it correctly, suggest that MediaWiki has never been able to satisfactory integrate the data caching feature of Turck in a stable or satisfactory way, causing different people to have different problems with it. Thus, you shouldn't enable this option in LocalSettings.php. You might be concerned about losing cache capability, but (as I understand) even if you disable the option, you still get the benefit of Turck caching compiled php scripts, which is a big benefit. _______________________________________________ MediaWiki-l mailing list MediaWiki-l(a)Wikimedia.org http://mail.wikipedia.org/mailman/listinfo/mediawiki-l

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David Liontooth

11:16 p.m.

New subject: [Mediawiki-l] Activating Turck MMCache after installation

Carlton B wrote:

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-----Original Message----- From: mediawiki-l-bounces(a)Wikimedia.org [mailto:mediawiki-l-bounces@Wikimedia.org]On Behalf Of David Liontooth Sent: Tuesday, June 21, 2005 4:13 AM To: MediaWiki announcements and site admin list Subject: Re: [Mediawiki-l] Activating Turck MMCache after installation MHart wrote:

I enable mmcache on all sites - I have about 5 running on one server, all with mmcache enabled, without any problems. I did not, however, attempt to go back to sites that were previously setup and get them running with mmcache, rather I re-setup the scripts in a different folder and updated the server settings. - MHart

Are you using a separate database for each wiki? If you are, you shouldn't be running into the problem I ran into (if I understand Carlton right). If you're using the same database, that would be interesting. http://mail.wikipedia.org/mailman/listinfo/mediawiki-l

Just want to clarify that in my problem, there was only a single wiki involved. Mine was a problem with calls to Turck data caching simply failing most of the time and the response was, well, Turck might not work so hot with mediawiki in some cases, but nobody's thrashed it out as much as we'd like. (to paraphrase what I was told).

OK, thanks. I've not had problems with Turck on a single wiki within a database shared by several others, but I haven't exactly stress-tested it. As I don't clearly need the extra performance, I'll turn it off in LocalConfig for now. Dave

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MHart

21 Jun 21 Jun

1:33 p.m.

New subject: [Mediawiki-l] Activating Turck MMCache after installation

Separate database - same machine - MHart ----- Original Message ----- From: "David Liontooth" <liontooth(a)cogweb.net> To: "MediaWiki announcements and site admin list" <mediawiki-l(a)Wikimedia.org> Sent: Monday, June 20, 2005 3:13 PM Subject: Re: [Mediawiki-l] Activating Turck MMCache after installation

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MHart wrote:

I enable mmcache on all sites - I have about 5 running on one server, all with mmcache enabled, without any problems. I did not, however, attempt to go back to sites that were previously setup and get them running with mmcache, rather I re-setup the scripts in a different folder and updated the server settings. - MHart

Are you using a separate database for each wiki? If you are, you shouldn't be running into the problem I ran into (if I understand Carlton right). If you're using the same database, that would be interesting. Dave

----- Original Message ----- From: "Carlton B" <carltonb(a)mindspring.com> To: "MediaWiki announcements and site admin list" <mediawiki-l(a)Wikimedia.org> Sent: Monday, June 20, 2005 4:55 AM Subject: RE: [Mediawiki-l] Activating Turck MMCache after installation

-----Original Message----- From: mediawiki-l-bounces(a)Wikimedia.org [mailto:mediawiki-l-bounces@Wikimedia.org]On Behalf Of David Liontooth Sent: Monday, June 20, 2005 5:44 PM To: mediawiki-l(a)Wikimedia.org Subject: [Mediawiki-l] Activating Turck MMCache after installation When I set up my first MediaWiki (nice work, btw!), I got "Turck MMCache not installed", even though I had just installed it. (I assume some app or daemon needed to be reloaded to detect it -- which one?) Later, when I installed a second wiki, Turck MMCache was detected, and I activated it. Seeing the result of the activation in LocalSettings.php, I uncommented the same line for the other wiki -- $wgUseTurckShm = function_exists( 'mmcache_get' ) && php_sapi_name() == 'apache'; The effect was a messed up cache function -- the second wiki's Main_Page would consistently display in the first wiki. If I selected [Edit] and Preview, I would see the first wiki's real Main_Page intact, but saving it would revert the display to the second wiki's front page. Nikerabbit on #mediawiki irc diagnosed it and I fixed the problem easily -- whew. But how do I properly activate Turck MMCache for a wiki that is already installed?

This does not answer your question at all, but I experienced some frustrating problems using Turck MMCache and I advise not using it if you're having problems with it. The answer I received here, if I understood it correctly, suggest that MediaWiki has never been able to satisfactory integrate the data caching feature of Turck in a stable or satisfactory way, causing different people to have different problems with it. Thus, you shouldn't enable this option in LocalSettings.php. You might be concerned about losing cache capability, but (as I understand) even if you disable the option, you still get the benefit of Turck caching compiled php scripts, which is a big benefit. _______________________________________________ MediaWiki-l mailing list MediaWiki-l(a)Wikimedia.org http://mail.wikipedia.org/mailman/listinfo/mediawiki-l

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David Liontooth

7:05 p.m.

New subject: [Mediawiki-l] Re: Activating Turck MMCache after installation

Tim Starling wrote:

...

David Liontooth wrote:

The effect was a messed up cache function -- the second wiki's Main_Page would consistently display in the first wiki. If I selected [Edit] and Preview, I would see the first wiki's real Main_Page intact, but saving it would revert the display to the second wiki's front page.

This is probably because you were using a table prefix to distinguish the two wikis, rather than a different database. This is not supported properly by MediaWiki, and will be a problem whether you use Turck or Memcached. The DB-based cache is the only one that's immune, since it's stored in a table with a prefixed name. -- Tim Starling

Appreciate the explanation -- I'm in fact using a single database. Will there be a problem if I activate Turck for one of the wikis only? So far that doesn't seem to be causing problems. It would be useful if the documentation on the installation pointed this out. Dave

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Brion Vibber

5:18 p.m.

New subject: [Mediawiki-l] Re: Activating Turck MMCache after installation

Ed W wrote:

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Since Turck is now dead and replaced by eaccelerator, are there any caveats in using that instead?

Since eaccelerator is Turck with a new name, caveats are the same. -- brion vibber (brion @ pobox.com)

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