Re: the " 'official' point of view" expressed by kernelnewbies.org regarding reiser4 inclusion

Jeff V. Merkey
2006-07-31T23:18:40Z

Nate Diller wrote:

> On 7/31/06, Jeff V. Merkey <jmerkey@wolfmountaingroup.com> wrote:
>
>> Gregory Maxwell wrote:
>>
>> > On 7/31/06, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> >
>> >> Its well accepted that reiserfs3 has some robustness problems in the
>> >> face of physical media errors. The structure of the file system
>> and the
>> >> tree basis make it very hard to avoid such problems. XFS appears
>> to have
>> >> managed to achieve both robustness and better data structures.
>> >>
>> >> How reiser4 compares I've no idea.
>> >
>> >
>> > Citation?
>> >
>> > I ask because your clam differs from the only detailed research that
>> > I'm aware of on the subject[1]. In figure 2 of the iron filesystems
>> > paper that Ext3 is show to ignore a great number of data-loss inducing
>> > failure conditions that Reiser3 detects an panics under.
>> >
>> > Are you sure that you aren't commenting on cases where Reiser3 alerts
>> > the user to a critical data condition (via a panic) which leads to a
>> > trouble report while ext3 ignores the problem which suppresses the
>> > trouble report from the user?
>> >
>> > *1) http://www.cs.wisc.edu/adsl/Publications/iron-sosp05.pdf
>>
>> Hi Gregory, Wikimedia Foundation and LKML?
>>
>> How's Wikimania going. :-)
>>
>> What he says is correct. I have seen some serious issues with reiserfs
>> in terms of stability and
>> data corruption. Resier is however FASTER, but the statement is has
>> robustness issues is accurate.
>> I was using reiserfs but we opted to make EXT3 the default for Solera
>> appliances, even when using Suse 10
>> due to issues I have seen with data corruption and hard hangs on RAID 0
>> read/write sector errors. I have
>> stopped using it for local drives and based everything on EXT3. Not to
>> say it won't get there eventually, but
>> file systems have to endure a lot of time in the field and deployment
>> befor they are ready for prime time.
>>
>> The Wikimedia appliances use Wolf Mountain, and I've tested it for about
>> 4 months with few problems, but
>> I only use it for hosting the Cherokee Langauge Wikipedia. It's
>> performance is several magnitudes better
>> than either EXT3 or ReiserFS. Despite this, for vertical wiki servers,
>> its ok to go out with, folks can specifiy
>> whether they want appliances with EXT3, Reiser, or WMFS, but iit's a
>> long way from being "cooked"
>> completely, though it does scale to 1 exabyte FS images.
>
>
> i've seen you mention the Wolf Mountain FS in other emails, but google
> isn't telling me a lot about it. Do you have a whitepaper? are there
> any published benchmark results? what sort of workloads do you
> benchmark?
>
> NATE
>
Wikipedia is the app for now. I have not done any benchmarks on the FS
side, just the capture side, and its been transferred to
another entity. I have no idea what they are naming it to, but I expect
you may hear about it soon. One of the incarnations
of it is Solera's DSFS which can be reviewed here:

www.soleranetworks.com

I can sustain 850 MB/S throughput from user space with it -- about 5 x
any other FS. On some hardware, I've broken
the 1.25 GB/S (gigabyte/second) windows with it.

Jeff