git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: Jonathan Nieder <jrnieder@gmail.com>
To: Jonathan Tan <jonathantanmy@google.com>
Cc: Jeff Hostetler <git@jeffhostetler.com>,
	git@vger.kernel.org, jeffhost@microsoft.com, peff@peff.net,
	gitster@pobox.com, markbt@efaref.net, benpeart@microsoft.com
Subject: Re: [PATCH 00/10] RFC Partial Clone and Fetch
Date: Wed, 3 May 2017 14:08:50 -0700	[thread overview]
Message-ID: <20170503210850.GG28740@aiede.svl.corp.google.com> (raw)
In-Reply-To: <2b1b504a-07c9-81b3-fed2-e9c029a5b284@google.com>

Hi,

Jonathan Tan wrote:

> The binary search to lookup a packfile offset from a .idx file
> (which involves disk reads) would take longer for all lookups (not
> just lookups for missing blobs) - I think I prefer keeping the lists
> separate, to avoid pessimizing the (likely) usual case where the
> relevant blobs are all already in local repo storage.

Another relevant operation is looking up objects by offset or
index_nr.  The current implementation involves building an in-memory
reverse index on demand by reading the idx file and sorting it by
offset --- see pack-revindex.c::create_pack_revindex.  This takes O(n
log n) time where n is the size of the idx file.

That said, it could be avoided by storing an on-disk reverse index
with the pack.  That's something we've been wanting to do anyway.

Thanks,
Jonathan

  reply	other threads:[~2017-05-03 21:08 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-08 18:50 [PATCH 00/10] RFC Partial Clone and Fetch git
2017-03-08 18:50 ` [PATCH 01/10] pack-objects: eat CR in addition to LF after fgets git
2017-03-08 18:50 ` [PATCH 02/10] pack-objects: add --partial-by-size=n --partial-special git
2017-03-08 18:50 ` [PATCH 03/10] pack-objects: test for --partial-by-size --partial-special git
2017-03-08 18:50 ` [PATCH 04/10] upload-pack: add partial (sparse) fetch git
2017-03-08 18:50 ` [PATCH 05/10] fetch-pack: add partial-by-size and partial-special git
2017-03-08 18:50 ` [PATCH 06/10] rev-list: add --allow-partial option to relax connectivity checks git
2017-03-08 18:50 ` [PATCH 07/10] index-pack: add --allow-partial option to relax blob existence checks git
2017-03-08 18:50 ` [PATCH 08/10] fetch: add partial-by-size and partial-special arguments git
2017-03-08 18:50 ` [PATCH 09/10] clone: " git
2017-03-08 18:50 ` [PATCH 10/10] ls-partial: created command to list missing blobs git
2017-03-09 20:18 ` [PATCH 00/10] RFC Partial Clone and Fetch Jonathan Tan
2017-03-16 21:43   ` Jeff Hostetler
2017-03-17 14:13     ` Jeff Hostetler
2017-03-22 15:16 ` ankostis
2017-03-22 16:21   ` Johannes Schindelin
2017-03-22 17:51     ` Jeff Hostetler
2017-05-03 16:38 ` Jeff Hostetler
2017-05-03 18:27   ` Jonathan Nieder
2017-05-04 16:51     ` Jeff Hostetler
2017-05-04 18:41       ` Jonathan Nieder
2017-05-08  0:15     ` Junio C Hamano
2017-05-03 20:40   ` Jonathan Tan
2017-05-03 21:08     ` Jonathan Nieder [this message]
  -- strict thread matches above, loose matches on Subject: below --
2017-03-08 17:37 Jeff Hostetler

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170503210850.GG28740@aiede.svl.corp.google.com \
    --to=jrnieder@gmail.com \
    --cc=benpeart@microsoft.com \
    --cc=git@jeffhostetler.com \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=jeffhost@microsoft.com \
    --cc=jonathantanmy@google.com \
    --cc=markbt@efaref.net \
    --cc=peff@peff.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
Code repositories for project(s) associated with this public inbox

	https://80x24.org/mirrors/git.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).