Re: [RFC 0/3] dumb HTTP transport speedups

Jakub Narębski [off-list ref] wrote:

W dniu 2016-07-11 o 22:51, Eric Wong pisze:

quoted

TL;DR: dumb HTTP clone from a certain badly-packed repo goes from
~2 hours to ~30 min memory usage drops from 2G to 360M


I hadn't packed the public repo at https://public-inbox.org/git
for a few weeks.  As an admin of a small server limited memory
and CPU resources but fairly good bandwidth, I prefer clients
use dumb HTTP for initial clones.

Hopefully the solution / workaround for large initial clone
problem utilizing bundles (`git bundle`), which can be resumably
transferred, would get standarized and automated.

I've been hoping to look at this more in coming weeks/months.
It would be nice if bundles and packs could be unified somehow
to avoid doubling storage on the server.

Do you use bitmap indices for speeding up fetches?

Yes, but slow clients are still a problem since big responses
keeps memory-hungry processes running while trickling
(or waste disk space buffering the pack output up front)

Static packfiles/bundles are nice since all the clients can
share the same data on the server side as it's trickled out.

BTW. IMVHO the problem with dumb HTTP is the latency, not extra
bandwidth needed...

I enabled persistent connections for 404s on loose objects for
this reason :)  We should probably be doing it across the board
on 404s, just haven't gotten around to it...

Increasing default parallelism should also help; but might hurt
some servers which can't handle many connections...
Hard to imagine people using antiquated prefork servers for
slow clients in a post-Slowloris world, but maybe it happens?