[Gluster-users] Files per directory

[Mohit Anchlia]

Thanks for sharing. It looks like 3.5 million files are directly
placed under /export/read-write/g0{1,2} on 2 servers. I am assuming
performance stays the same as no. of files increase.

Couple of more questions:

Did you also consider using RAID 0 over these 2 disks on the same host?
Do you know what happens when a new node is added. Since gluster uses
elastic hashing does it still work or does new node throws off the
hashing algorithm. I am wondering how gluster is able to retrieve old
files after adding new node because now it's hashing accross new
nodes.

Thanks again and keep us posted!

I will be starting similar testing in next 2 weeks also.


On Wed, Mar 9, 2011 at 10:53 AM, Burnash, James <jburnash at knight.com> wrote:
> I'm running ext4 on CentOS 5.5. Each storage server has two bricks, each in their own directory, mounted as straight partitions. No LVM used in this config.
>
> I did find that I had to keep the ext4 format and mount options simple to avoid crashes that I encountered with more "tuned" configs.
>
> # create ext4 read-write storage
>
> yum -y install e4fsprogs e4fsprogs-libs e4fsprogs-devel dmapi
>
> create a single partition on each disk, maximum size, primary type
>
> time mke4fs -F -L g01 -v -j /dev/cciss/c1d0p1
> time mke4fs -F -L g02 -v -j /dev/cciss/c2d0p1
>
> mkdir -p /export/read-write/g0{1,2}
> mount -t ext4 /dev/cciss/c1d0p1 /export/read-write/g01
> mount
> mount -t ext4 /dev/cciss/c2d0p1 /export/read-write/g02
>
> fgrep read-write /etc/fstab
> /dev/cciss/c1d0p1       /export/read-write/g01  ext4    defaults        0 0
> /dev/cciss/c2d0p1       /export/read-write/g02  ext4    defaults        0 0
>
> James Burnash, Unix Engineering
>
> -----Original Message-----
> From: Mohit Anchlia [mailto:mohitanchlia at gmail.com]
> Sent: Wednesday, March 09, 2011 1:15 PM
> To: Burnash, James; gluster-users at gluster.org
> Subject: Re: [Gluster-users] Files per directory
>
> Thanks! Is this on ext3 or ext4? Are all these files in mount
> directory or they are in sub directories. On glusterfs does it matter
> if all the files are placed in same directory? Generally from what
> I've seen in the past is that multiple no. of subdirs are recommended
> to improve performance.
>
> On Wed, Mar 9, 2011 at 9:59 AM, Burnash, James <jburnash at knight.com> wrote:
>> I'm going through a rebalance operation now on my "small" Glusterfs storage pool - 2 servers, 4 bricks, 30TB of total storage, 175 native Glusterfs clients.
>>
>> Current files checked is at 3.5 million - a lot of those are in the 1-1.5GB size range.
>>
>> Hopefully that is of some help - more stats to follow as I get a chance to document them ...
>>
>> James Burnash, Unix Engineering
>>
>>
>> -----Original Message-----
>> From: gluster-users-bounces at gluster.org [mailto:gluster-users-bounces at gluster.org] On Behalf Of Mohit Anchlia
>> Sent: Wednesday, March 09, 2011 12:47 PM
>> To: gluster-users at gluster.org
>> Subject: Re: [Gluster-users] Files per directory
>>
>> It will be good if I can get some suggestion from people who already
>> have millions of files on glusterFS.
>>
>> On Mon, Mar 7, 2011 at 4:11 PM, Mohit Anchlia <mohitanchlia at gmail.com> wrote:
>>> Is there any recommendation about how many files should be stored in
>>> one directory in glusterFS? In my experience I've seen spreading files
>>> accross many directories helps, but I am not sure if it's same with
>>> glusterFS.
>>>
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