file_handle_cache branch ready for review

For interested parties,

Work on said branch is done so far and I think
it is generally ready for being merged into /trunk.
But it is certainly a good idea to give it some
detailed review, in particular with regard to side-
effects on e.g. FSFS recovery code.

What it does in a nutshell:

* to FSFS svn_fs_t, attaches a cache for open file
   handles to reduce the number of open, lseek,
   read and close operations
* svnserve CL and apache config option to set
   the per-process maximum of cached handles
   (default: 16)

* use cached file handles for r/o access to revision
   files in FSFS
* notify the cache after revision files have been
   written ("flush" cache entries for these files)

With the repository on a linux RAM disk, it speeds
up a "cold" export of TSVN /trunk by approx. 10%.
Slower disks may show larger gains.

If there are no major objections, I would like to merge
the code into /trunk around mid-January.

-- Stefan^2.
Received on 2011-12-18 19:47:37 CET