37 | | - `default_daysback` set to a high value might introduce quite some load, depending on the activity. |
38 | | Pick an appropriate value for your site. |
39 | | - the default `max_daysback` can be inappropriate, eg allowing 90 days for a site with lots |
40 | | of activity might be too much. Don't hesitate to reduce it, especially now that Trac supports paging |
41 | | - any setting other than `changeset_show_files = 0` can be expensive, depending on the quantity of changesets to process |
| 37 | - `default_daysback` set to a high value might introduce quite some load, depending on the activity. Pick an appropriate value for your site. |
| 38 | - the default `max_daysback` can be inappropriate, eg allowing 90 days for a site with lots of activity might be too much. Don't hesitate to reduce it, especially now that Trac supports paging. |
| 39 | - any setting other than `changeset_show_files = 0` can be expensive, depending on the quantity of changesets to process. |
65 | | - INFO messages: '''Reloading environment due to configuration change''' [[br]] |
66 | | If you find lots of such lines, or even worse, if they appear systematically, then chances are that you're using a plugin which does systematic updates to the configuration file [TracIni trac.ini], and this will in turn trigger a full environment reload at the next request. That can slow down the performance a lot, to the level of TracCgi. See ticket:7490#comment:102 and follow-up. |
67 | | - INFO messages: '''rev ![321] != cached rev ![123]''' (other revision numbers for you, of course) [[br]] |
68 | | If you find such lines ''and the `cached rev` value doesn't change'', this corresponds to a repository resync failure, which results in a resync attempt for every request (see ticket:7490#comment:36); often as a result of the "prohibited" MySQL/MyISAM combination (#8067). |
69 | | - WARNING message: '''Slow mail submission''' [[br]] |
70 | | A mis-configured or simply slow mail server make Trac appear very slow (#3220). |
| 63 | - INFO messages: '''Reloading environment due to configuration change''': [[br]] |
| 64 | If you find many such lines, or even worse, if they appear systematically, then chances are that you're using a plugin which does systematic updates to the configuration file [TracIni trac.ini], and this will in turn trigger a full environment reload at the next request. That can slow down the performance a lot, to the level of TracCgi. See ticket:7490#comment:102 and follow-up. |
| 65 | - INFO messages: '''rev ![321] != cached rev ![123]''' (other revision numbers for you, of course:) [[br]] |
| 66 | If you find such lines ''and the `cached rev` value doesn't change'', then this corresponds to a repository resync failure, which results in a resync attempt for every request (see ticket:7490#comment:36); often as a result of the "prohibited" MySQL/MyISAM combination (#8067). |
| 67 | - WARNING message: '''Slow mail submission''': [[br]] |
| 68 | A mis-configured or simply slow mail server makes Trac appear very slow (#3220). |
75 | | - After the adoption of the [genshi:Genshi] template engine in [/milestone/0.11 Trac 0.11] in 2008, some associated performance issues were solved (#6614). |
76 | | - In Trac 1.3 the Jinja template engine was adopted and performance is improved over Genshi (#12639). |
77 | | - Many plugins still use Genshi templates, which are supported for compatibility until Trac 1.5.1. |
78 | | - Plugins that use the `ITemplateStreamFilter` interface prevent the performance improvements gained by using Jinja. |
| 73 | |
| 74 | In Trac 1.3 the Jinja template engine was adopted and performance has improved over Genshi (#12639). |
| 75 | - Many plugins still use Genshi templates, which are supported for compatibility until Trac 1.5.1. |
| 76 | - Plugins that use the `ITemplateStreamFilter` interface eliminate the performance improvements gained by Jinja. |
87 | | - There was a bug up to 0.11.4 which could cause 100% CPU usage once in a while on some platforms. See #7785, which was thought to be fixed in 0.11.5, but re-opened since. |
88 | | - Some plugins seem to degrade performance, see ["TracDev/Performance/0.11.5#customizationsandplugins"]. |
| 85 | - There was a bug up to Trac 0.11.4 which could cause 100% CPU usage once in a while on some platforms. See #7785, which was thought to be fixed in 0.11.5, but re-opened since. |
| 86 | - Some plugins seem to degrade performance, see ["TracDev/Performance/0.11.5#customizationsandplugins"]. |
| 87 | - The more plugins, the higher the potentiality for performance degradation in unpredictable ways: install, test and use plugins in a staggered fashion to better understand since when and how performance has degraded. |