2006-01-08 22:24:03

by Jan Engelhardt

[permalink] [raw]
Subject: reiserfs mount time

Hi,


brought to attentino on an irc channel, reiser seems to have the largest
mount times for big partitions. I see this behavior on at least two
machines (160G, 250G) and one specially-crafted virtual machine
(a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
from http://linuxgazette.net/122/TWDT.html#piszcz
So, any hint from the reiserfs developers how come reiserfs takes so long?
Standard mkreiserfs options (none extra passed).


Jan Engelhardt
--


2006-01-08 22:34:25

by Tomasz Torcz

[permalink] [raw]
Subject: Re: reiserfs mount time

On Sun, Jan 08, 2006 at 11:24:02PM +0100, Jan Engelhardt wrote:
> Hi,
>
>
> brought to attentino on an irc channel, reiser seems to have the largest
> mount times for big partitions. I see this behavior on at least two
> machines (160G, 250G) and one specially-crafted virtual machine
> (a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).

My 177 GiB partition on SATA disc takes about 10 seconds to mount. It
is 1/3 of Linux boot time :(

--
Tomasz Torcz 72->| 80->|
[email protected] 72->| 80->|


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2006-01-08 23:31:23

by Lee Revell

[permalink] [raw]
Subject: Re: reiserfs mount time

On Sun, 2006-01-08 at 23:24 +0100, Jan Engelhardt wrote:
> Hi,
>
>
> brought to attentino on an irc channel, reiser seems to have the largest
> mount times for big partitions. I see this behavior on at least two
> machines (160G, 250G) and one specially-crafted virtual machine
> (a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
> Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
> from http://linuxgazette.net/122/TWDT.html#piszcz
> So, any hint from the reiserfs developers how come reiserfs takes so long?
> Standard mkreiserfs options (none extra passed).
>

reiser3 or reiser4?

Lee

2006-01-09 16:18:27

by Jan Engelhardt

[permalink] [raw]
Subject: Re: reiserfs mount time

>>
>> brought to attentino on an irc channel, reiser seems to have the largest
>> mount times for big partitions. I see this behavior on at least two
>> machines (160G, 250G) and one specially-crafted virtual machine
>> (a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
>> Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
>> from http://linuxgazette.net/122/TWDT.html#piszcz
>> So, any hint from the reiserfs developers how come reiserfs takes so long?
>> Standard mkreiserfs options (none extra passed).
>
>reiser3 or reiser4?

For my case, reiser3.

(According to that pic link (from irc) also reiser4, but I'm inclined not
to believe that one.)


Jan Engelhardt
--
| Alphagate Systems, http://alphagate.hopto.org/
| jengelh's site, http://jengelh.hopto.org/

2006-01-09 16:21:19

by Lee Revell

[permalink] [raw]
Subject: Re: reiserfs mount time

On Mon, 2006-01-09 at 17:18 +0100, Jan Engelhardt wrote:
> >>
> >> brought to attentino on an irc channel, reiser seems to have the largest
> >> mount times for big partitions. I see this behavior on at least two
> >> machines (160G, 250G) and one specially-crafted virtual machine
> >> (a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
> >> Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
> >> from http://linuxgazette.net/122/TWDT.html#piszcz
> >> So, any hint from the reiserfs developers how come reiserfs takes so long?
> >> Standard mkreiserfs options (none extra passed).
> >
> >reiser3 or reiser4?
>
> For my case, reiser3.
>
> (According to that pic link (from irc) also reiser4, but I'm inclined not
> to believe that one.)

reiser3 is in maintenance mode so is unlikely to be fixed. If you still
have the problem with reiser4 then they would probably like to hear
about it.

Lee

2006-01-14 20:34:12

by Jan Kara

[permalink] [raw]
Subject: Re: reiserfs mount time

Hello,

> brought to attentino on an irc channel, reiser seems to have the largest
> mount times for big partitions. I see this behavior on at least two
> machines (160G, 250G) and one specially-crafted virtual machine
> (a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
> Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
> from http://linuxgazette.net/122/TWDT.html#piszcz
> So, any hint from the reiserfs developers how come reiserfs takes so long?
> Standard mkreiserfs options (none extra passed).
If I remember correctly, the problem is reiserfs loads bitmaps on mount
and that takes most of the time. Jeff Mahoney <[email protected]> has
patches fixing this but I think Hans rejected them because he wants only
bugfixes in reiser3...

Honza

--
Jan Kara <[email protected]>
SuSE CR Labs

2006-01-14 20:40:51

by Jeff Mahoney

[permalink] [raw]
Subject: Re: reiserfs mount time

Jan Kara wrote:
> Hello,
>
>
>>brought to attentino on an irc channel, reiser seems to have the largest
>>mount times for big partitions. I see this behavior on at least two
>>machines (160G, 250G) and one specially-crafted virtual machine
>>(a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
>>Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
>>from http://linuxgazette.net/122/TWDT.html#piszcz
>>So, any hint from the reiserfs developers how come reiserfs takes so long?
>>Standard mkreiserfs options (none extra passed).
>
> If I remember correctly, the problem is reiserfs loads bitmaps on mount
> and that takes most of the time. Jeff Mahoney <[email protected]> has
> patches fixing this but I think Hans rejected them because he wants only
> bugfixes in reiser3...

Yeah, that's the right analysis. ReiserFS caches bitmaps on mount and
for large file systems it can take a quite a long time. I've heard
reports of up to 15 minutes on multi-TB file systems.

As far as these patches getting accepted, Hans was opposed to them
initially, but emailed in September saying he decided that they should
be accepted after all.

These were against 2.6.12.1, and I remerged and split the patches out
yesterday evening. I'm going to do a bit of testing and send them out on
Monday for inclusion in -mm.

-Jeff

--
Jeff Mahoney
SUSE Labs

2006-01-14 21:37:50

by Jan Engelhardt

[permalink] [raw]
Subject: Re: reiserfs mount time


>>>brought to attentino on an irc channel, reiser seems to have the largest
>>>mount times for big partitions. I see this behavior on at least two
>>>machines (160G, 250G) and one specially-crafted virtual machine
>>>(a 1.9TB disk / 1.9TB partition - took somewhere over 120 seconds).
>>>Here's a dig http://linuxgazette.net/122/misc/piszcz/group001/image002.png
>>>from http://linuxgazette.net/122/TWDT.html#piszcz
>>>So, any hint from the reiserfs developers how come reiserfs takes so long?
>>>Standard mkreiserfs options (none extra passed).
>>
>> If I remember correctly, the problem is reiserfs loads bitmaps on mount
>> and that takes most of the time. Jeff Mahoney <[email protected]> has
>> patches fixing this but I think Hans rejected them because he wants only
>> bugfixes in reiser3...
>
>Yeah, that's the right analysis. ReiserFS caches bitmaps on mount and
>for large file systems it can take a quite a long time.

And quite some memory. But never mind, I already migrated by now.
(Not because of mount time, but other factors.)



Jan Engelhardt
--