linux-kernel - Re: [RFC][PATCH 6/6] automatic tuning applied to some kernel components

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]

Message-ID: <45D406BF.2060009@bull.net>
Date:	Thu, 15 Feb 2007 08:07:43 +0100
From:	Nadia Derbey <Nadia.Derbey@...l.net>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
Cc:	Andrew Morton <akpm@...l.org>, linux-kernel@...r.kernel.org
Subject: Re: [RFC][PATCH 6/6] automatic tuning applied to some kernel components

Eric W. Biederman wrote:
> Nadia Derbey <Nadia.Derbey@...l.net> writes:
> 
> 
>>So, should I understand from this that automatic tuning and the AKT framework
>>itself would make sense, given that I find the rigth tunables it should be
>>applied to?
> 
> 
> Sort of.  The concept of things tuning themselves automatically makes
> a lot of sense.
> 
> I'm not at all certain about tunables being exported just to be hidden
> again.  Ideally you don't even want the fact that these things are
> varying visible to the user.
> 
> So I think that if you can find a good example that cannot be solved
> better another way, you can build a case for your framework.
> Currently I am doubt you can find such a case.
> 
> 
>>Actually, dont' know if you had the opportunity to read all the patches, but
>>there are 2 other tunables AKT is proposed to be applied to:
>>. max_threads, the tunable limit on nr_threads
>>. max_files, the tunable limit on nr_files
> 
> 
> At a quick glance max_threads and max_files appear even more to be
> DOS limits and not tunables and even less applicable to needing any
> tuning at all.  My gut feel is at worst these values may need a little
> better boot time defaults but otherwise they the should be good.
> 
But, what do you do with Oracle that's asking maxfiles to be set to 
0x10000, while the default value might be enough for a system that's not 
running Oracle.
I'm afraid that giving boot time values to the max_* tunables we will 
loose all the benefits from /proc (or /sys): it is impossible to 
anticipate what an OS will be used for. So allowing such things to be 
changed without having to reboot the machine is in my mind quite a 
powerful feature we should keep taking adavntage of.

Regards,
Nadia
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/