From: Alex Elsayed <eternaleye@gmail.com>
To: ceph-devel@vger.kernel.org
Subject: Re: Blueprint: Add LevelDB support to ceph cluster backend store
Date: Tue, 30 Jul 2013 22:54:15 +0000 [thread overview]
Message-ID: <kta8j6$51o$1@ger.gmane.org> (raw)
In-Reply-To: C0D1D705-4B4F-4189-ACBF-4C39D80984DA@gmail.com
I posted this as a comment on the blueprint, but I figured I'd say it here:
The thing I'd worry about here is that LevelDB's performance (along with
that of various other K/V stores) falls off a cliff for large values.
Symas (who make LMDB, used by OpenLDAP) did some benchmarking that shows
drastic performance loss with 100KB values on both read and write:
http://symas.com/mdb/microbench/#sec4
It's not just disk latency, either - an SSD showed the same behavior:
http://symas.com/mdb/microbench/#sec7
I'd recommend REALLY careful benchmarking with a variety of loads (and value
sizes).
next prev parent reply other threads:[~2013-07-31 5:50 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-07-31 3:10 Blueprint: Add LevelDB support to ceph cluster backend store Haomai Wang
2013-07-30 22:54 ` Alex Elsayed [this message]
2013-07-31 5:56 ` Gregory Farnum
2013-07-31 6:04 ` 袁冬
2013-07-31 6:07 ` 袁冬
2013-07-31 6:01 ` Sage Weil
2013-07-31 6:38 ` Haomai Wang
2013-08-27 23:01 ` Sage Weil
2013-08-28 14:12 ` Haomai Wang
2013-08-28 16:17 ` Sage Weil
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='kta8j6$51o$1@ger.gmane.org' \
--to=eternaleye@gmail.com \
--cc=ceph-devel@vger.kernel.org \
/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.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.