performance issues when viewing larger files

[theultramage@…]

There are numerous source code files in our project that are above the default limit (250kB).
When viewing these files, it takes a moment before they're generated and rendered by the browser. When using the 'annotate' option, this problem increases significantly. Here is a sample (server is a P733, using apache):

Original size: 200kB
Browser view: 800kB, generating time: 1 minute
Annotated view: 1500kB, generating time: 5 minutes

It gets far worse on files that are 400+kB (actually I don't even try that anymore).
Additionally, when viewing such an annotated page in Opera, the browser does 100% cpu load that doesn't stop until you close the page. Sometimes it also destabilizes the browser (needs restart).

Can anything be done in this regard?

[cboos]

There's certainly room for improvement:

• the blame.js Javascript code could certainly be optimized or could even disable itself for large files
• the generated HTML could be less verbose
  • there's the empty <span> problem (#4339)
  • the color code could eventually be done using class names instead of style attributes

Tentatively scheduling for 0.11.

[kirean@…]

I'm also having perfomance issues with annotate.

[kirean@…]

The annotate view in 0.11 looks cool, but if performance is effected I'll be stuck with ViewVC anyway. I would prefer this to be done in the same (fast) way as in ViewVC instead..

[cboos]

Well, until the performance issue gets fixed, maybe we could try to disable the javascript code for anything but small files:

trac/versioncontrol/templates/browser.html

@@ -27 +27 @@
                 range_max_secs: '$dir.range_max_secs'
             });
         </py:if>
-        <py:if test="file and file.annotate">
+        <py:if test="file and file.annotate and file.size &lt; 50000">
           enableBlame("${href.changeset()}/", "${path}");
         </py:if>
       });

I doubt this will be enough to fix the performance issue, but maybe it will make it more acceptable.

[cboos]

See also #7055.