Ubuntu 9.10 with ext4 filesystem on Linux RAID5, superb performance!

[ugo1]

I am using Ubuntu 9.10 64-bit server with ext4 on a RAID10 array (not RAID5). I tried to replicate the large file corruption bug by copying large files to/from the ext4 partition and comparing checksums before entrusting data to it. All the checksums were fine and I couldn't reproduce any problem on my system.

hi

here https://bugs.launchpad.net/ubuntu/+source/linux/+bug/453579 the ext4 bug

Ugo

 

[msl]

hi

here https://bugs.launchpad.net/ubuntu/+source/linux/+bug/453579 the ext4 bug

Ugo

Yes, that is exactly the bug I was talking about. It does not exist on my system.

 

[sammynl]

Hi Sammy - I built similar setup using ubuntu 9.10 64 bit, however, im getting only max 19mb/s from a vista client

Hi zhamrock,

Sorry for the late reply i haven't been here for a while but glad you found the bottleneck together with 00Roush and others. Not surpised it's the client!

Maybe nice to add to the thread, I found that the chunksize used for the array makes huge differences in performance. There is a good link describing how much impact chuncksize has: Raid and chunksize performance tables. It's a very good article worth reading!

As far as network is concerned I use a Netgear WNR3500 Gigabit router, CAT6 cabling and both on the client and NAS Onboard PCI-Express Gigabit NIC's.

I found tuning the NAS with smb.conf modifications not useful, Ubuntu has the best defaults. What you can do is enable the "Avoid updating last access time" option for the raid mount folder and the shares using Webmin.

And last but I think not least, the more disks in the array the faster it gets, Ubuntu RAID5 is very happy with 5 or even better 6 disks.

Regards, Sammy.

 

[ugo1]

Question

Which software raid 5 performance I can expect from this configuration:

1- CPU QX6700
2- 8 GB of Ram
3- 3xWestern digital 1T RE3 disk
4- adaptec 280

I can excced in write / read the 100MB/S (mode dream on)?

Regards

Ugo