linux-kernel - Re: performance delta after VFS i_mutex=>i

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:	Mon, 06 Jun 2016 23:22:52 -0400
From:	Valdis.Kletnieks@...edu
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Waiman Long <waiman.long@....com>,
	Dave Hansen <dave.hansen@...el.com>,
	"Chen, Tim C" <tim.c.chen@...el.com>,
	Ingo Molnar <mingo@...hat.com>,
	Davidlohr Bueso <dbueso@...e.de>,
	"Peter Zijlstra (Intel)" <peterz@...radead.org>,
	Jason Low <jason.low2@...com>,
	Michel Lespinasse <walken@...gle.com>,
	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
	Waiman Long <waiman.long@...com>,
	Al Viro <viro@...iv.linux.org.uk>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: performance delta after VFS i_mutex=>i_rwsem conversion

On Mon, 06 Jun 2016 14:20:32 -0700, Linus Torvalds said:

> I guess some "concurrent readdir with unlink" load would show that
> behavior, but is it _realistic_? No idea. Let's not worry about it too
> much until somebody shows a reason to worry.

I've seen Makefiles where 'make clean' does a 'find . -name "*.o" | xargs rm'.

But if somebody is doing that often enough against cache-cold directory trees
to matter, they have bigger problems (like learning how to properly develop
code using 'make').  So unless performance is *so* bad it triggers the lockup
detector, it's probably OK....


Content of type "application/pgp-signature" skipped