Re: ufs multilabel performance (fwd)

From: O. Hartmann <ohartman_at_zedat.fu-berlin.de>
Date: Sun, 15 Apr 2012 21:30:26 +0200
Am 04/15/12 15:59, schrieb Richard Kojedzinszky:
> Thank you for the reply.
> 
> Unfortunately, dont know why, but on my xen virtualised environment,
> fbsd amd64 domU performs much slower, not only 30 times. Without
> multilabel, file creation speed is around 2500/s, but with multilabels
> enabled, it is only 15/s (!). so it is more than 100 times slower.
> 
> And anyway freebsd is known to be fast as well, as functional. The power
> to serve. :)
> 
> But in my environment, 15/s file creation is very-very slow. The
> hardware is a q6700 cpu with 4G ram, 2x1T sata disks in raid1, the host
> runs linux. I think with this hw the mentioned speed is really slow.
> 
> Regards,
> 
> 
> Kojedzinszky Richard
> Euronet Magyarorszag Informatikai Zrt.
> 
> On Sun, 15 Apr 2012, O. Hartmann wrote:
> 
>> Date: Sun, 15 Apr 2012 13:20:23 +0200
>> From: O. Hartmann <ohartman_at_zedat.fu-berlin.de>
>> To: Richard Kojedzinszky <krichy_at_tvnetwork.hu>
>> Cc: freebsd-security_at_freebsd.org
>> Subject: Re: ufs multilabel performance (fwd)
>>
>> Am 04/14/12 21:37, schrieb Richard Kojedzinszky:
>>> Dear list,
>>>
>>> Although it is not only security-related question, I did not get any
>>> answer from freebsd-performance. The original question is below.
>>>
>>> Can someone give some advice?
>>>
>>> Thanks in advance,
>>>
>>>
>>> Kojedzinszky Richard
>>> Euronet Magyarorszag Informatikai Zrt.
>>>
>>> ---------- Forwarded message ----------
>>> Date: Thu, 10 Nov 2011 06:16:57 +0100 (CET)
>>> From: Richard Kojedzinszky <krichy_at_tvnetwork.hu>
>>> To: freebsd-performance_at_freebsd.org
>>> Subject: ufs multilabel performance
>>>
>>> Dear List,
>>>
>>> I've noticed that when I enable multilabel on an fs, a file creation
>>> gets around 20-30 times slower than without multilabel set.
>>>
>>> This one-liner can be used to test the differences:
>>> $ truss -D perl -e 'open(F, ">$_.file") for 1 .. 1000'
>>
>> Same here, creating files seems to be 10 - 30 times slower with
>> multilabels as it is without.
>>
>> But as several posts and discussions reflects, FreeBSD isn't supposed to
>> be fast although it is claimed that writing is the major than reading;
>> FBSD should serve functionality.
>>>
>>> And one can see that the open call takes much more when multilabel is
>>> set on an fs. It seems that only file creation needs that many time,
>>> when a file exists it is opened much faster.
>>>
>>> Could someone acknowledge this, and have some suggestions how to make it
>>> faster?
>>>
>>> Regards,
>>>
>>>
>>> Kojedzinszky Richard
>>> TvNetWork Nyrt.
>>> E-mail: krichy (at) tvnetwork [dot] hu
>>> PGP: 0x54B2BF0C8F59B1B7
>>>   Fingerprint = F6D4 3FFE AF03 CACF 0DCB  46A1 54B2 BF0C 8F59 B1B7

At the moment, I'm troubled with a nasty kernel bug on all FreeBSD 10
boxes I have spare to test.

I just tried to reproduce your observation and as far as I can go with
my experience, I can confirm that by using your perl script.

I'd like to test this again with a small C program.

I can only test the issue (test is too far optimistic, it's simply a
reproduction of your observation) on FreeBSD 10, the only remaining
FreeBSD server at our department is running FBSD 9-STABLE/amd64 and "in
production", so changing multilabel support is a bit harsh at the moment.


Sorry about crossposting, but I think this belongs more to CURRENT and
PERFORMANCE than SECURITY.

Regards,
Oliver


Received on Sun Apr 15 2012 - 17:30:33 UTC

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