Re: [Monotone-devel] times to load various things from the database

[Nathaniel Smith]

On Sat, Jan 10, 2009 at 10:58 PM, Derek Scherger <address@hidden> wrote:
> However, reading rosters is comparably slow.
[...]
> There is some improvement here but not all that much. It seems that long
> delta chains are likely a bigger factor. After reconstructing an old
> roster with a long delta chain (600 deltas), the roster for the next
> revision is reconstructed by rebuilding essentially the same delta chain
> (599 deltas) and applying it again.

Right, roster deltas themselves are tiny, and therefore quick to parse
(they're basically like revisions).  The problem in profiles has
always been a combination of poor access patterns/caching, and the
overhead of copying the whole large roster structure in-memory before
applying the small delta.

-- Nathaniel