Listman wrote:
>
> sounds like a nice feature, thx!
>
> just in case the performance hit is significant is there switch to
> disable this?
There isn't a switch, per se, but the filesystem is not packed by default. In
order to pack the filesystem, an administrator will need to upgrade the
repository to a modern enough format, and then run 'svnadmin pack'. Once a
repository is packed, it can't be packed. Or at least, we don't yet have a
script to do that, though I suppose it'd be possible to write one.
> On Nov 26, 2008, at 6:11 PM- Nov 26, 2008, Hyrum K. Wright wrote:
>
>> Hi all.
>>
>> As of r34446, the implementation of packing on fsfs is functionally
>> complete on
>> the fsfs-pack branch. For those that don't know, packing consists of
>> mushing
>> all the individual rev files in a completed shard into one file, thus
>> eliminating the inode penalty for that entire shard. Packing a
>> trunk-generated
>> copy of the ASF repository saved about 1 GB on a 24 GB repo. There
>> may be
>> additional performance benefits in dealing with a much smaller set of
>> rev files
>> (OS caching, etc.), but I haven't yet investigated that.
>>
>> This comes at a cost: the offsets of revisions in the pack file are
>> stored
>> separately, and thus require an additional open/seek to get that
>> information.
>> Also, determining whether a revision is stored in a pack file or not also
>> requires additional I/O. I think that most of this can be eliminated
>> with
>> caching and heuristics, but those haven't yet been implemented.
>>
>> I'm not currently planning on including this functionality in 1.6, as
>> it's kinda
>> biggish feature, the optimizations aren't yet in place, and I feel
>> like merging
>> right before we branch 1.6.x could be a bit destabilizing. However, I
>> could
>> easily be talked into it. :)
>>
>> Anyway, I'm soliciting feedback on the implementation and usage of
>> this feature.
>> Comments welcome.
>>
>> -Hyrum
>>
>
>
Received on 2008-11-27 14:33:33 CET