netdev - Re: POHMELFS high performance network filesystem. Transactions, failover, performance.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 14 May 2008 17:37:58 -0400
From:	Jeff Garzik <jeff@...zik.org>
To:	Evgeniy Polyakov <johnpol@....mipt.ru>,
	Sage Weil <sage@...dream.net>, Jeff Garzik <jeff@...zik.org>,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: Re: POHMELFS high performance network filesystem. Transactions, failover,
 performance.

Jamie Lokier wrote:
> If you have a single data forwarder elected per client, then if one
> client generates a lot of traffic, you concentrate a lot of traffic to
> one network link and one CPU.  Sometimes it's better to elect several
> leaders per client, and hash requests onto them.  You diffuse CPU and
> traffic, but reduce opportunities to aggregate transactions into fewer
> message.  It's an interesting problem, again probably with different
> optimal results for different networks.


Definitely.  "several leaders" aka partitioning is also becoming 
increasing paired with efforts at enhancing locality of reference.  Both 
Google and Amazon sort their distributed tables lexographically, which 
[ideally] results in similar data being stored near each other.

A bit of an improvement over partitioning-by-hash, anyway, for some 
workloads.

	Jeff


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html