[CentOS] Filesystem for Maildir

Wed Nov 28 13:58:21 UTC 2007
Heitor A.M. Cardozo <heitor at centralserver.com.br>

Christopher Chan wrote:
> Heitor Augusto M Cardozo wrote:
>> Christopher Chan wrote:
>>> Heitor Augusto M Cardozo wrote:
>>>> Hi all,
>>>>
>>>> In last year, i had made some research and benchmarks based on 
>>>> CentOS 4 to know which filesystem is better for Maildir:  ReiserFS, 
>>>> XFS or EXT3.
>>>>
>>>> My conclusion was as follows:
>>>>
>>>> - EXT3: reliable but very slow to read many small files.
>>>> - ReiserFS: best performance but unreliable and bad recovery tools.
>>>> - XFS: My choice, good performance and reliability.
>>>
>>> I would contest the last two.
>>>
>> I had two bad experiences with ReiserFS in our Mail Server, 
>> reiserfsck is too slow and lost data.
>
> Well, not on that...reiserfs assumes perfect media according to the 
> complaints of some who use reiser so bad blocks could cause even the 
> entire loss of the filesystem...not to mention that RH and therefore 
> Centos (I wonder about plus...) does not support/maintain reiserfs.
>
>>
>> IMHO ReiserFS have the best performance for Maildir but its only safe 
>> on production if you´re sure that the system I/O will never fail.
>
> What does fsbench say? It has the best writing performance too?!?
>
No, according to the fsbench results, ReiserFS wins on Read Performance, 
but XFS is, approximately, four times more faster on write.

I said that the ReiserFS have the best performance based on my 
read/write server statics, where read requests are 70% of total I/O 
requests.

In production, with ReiserFS, the server load average was around 30% 
lower than XFS.

>>>>
>>>> On CentOS 5.0, a had the same benchmarks and now, EXT3 and XFS 
>>>> seems to had better or equivalent performance on Read and Create 
>>>> Random files. One of this tests, using bonnie++, show this:
>>>>
>>>> # bonnie++ -d /mnt/sdc1/testfile -s 8192 -m `hostname` -n 
>>>> 50:150000:5000:1000
>>>
>>> bonnie++? Not appropriate. Try this: 
>>> http://untroubled.org/benchmarking/2004-04/
>>>
>>> And add JFS to the mix. You will be surprised.
>>>
>> I already done tests with fsbench and the results on CentOS 4.5 were 
>> equivalent: the performance of XFS was much higher than EXT3.
>>
>> Then, i retest using fsbench, bonnie++ and iozone on CentOS 5.0, and 
>> the results now show the EXT3 (dir_index, noatime) with performance 
>> similar to XFS.
>
> Now that is very interesting.
>
>>>>
>>>> What i want to know is: Anyone use or recommend EXT3 for Maildir?
>>>
>>> If you do not have full blown battery back for write caches yes.
>>>
>>>>
>>>> My configuration: 3Ware 9650SE-8LPML, 8 drives SATA2  ST3500630AS 
>>>> 500GB on RAID 10.
>>>>
>>>
>>> Add BBU and XFS or JFS should do.
>> Yes, the BBU is installed and write_cache is enable. I will test JFS 
>> to compare.
>>
>> Thanks for your help.
>
> Please post your findings. :-)
>
I'm doing new tests with ReiserFS, XFS, EXT3 and JFS in CentOS 5. I will 
post soon as possible.

And sorry for my english...

Heitor A.M. Cardozo