RAID6 Rebuild time?

[insanity]

So, purchased a new 412. Dropped in 4 2TB Barracuda Drives and started using it. Everything was going great. Download center working great, grabbed new ISOs of Ubuntu, etc. However, on Sunday (2 days ago), Drive 4 failed. It's likely a manufacturing problem, so I return the drive (under replacement warranty time) and get the new drive (same model as others) into the 412. Shut down 412, restart... and it starts rebuilding... Great. Then I notice that it's... at 1%. An hour later.

... and rebuilding ...

... and rebuilding ...

... and rebuilding ...

It's now been 48 hours and I'm only 63% rebuilt.

Is this normal behavior? If not, what do I do?

Thanks.

[insanity]

Seriously? No one has any comments on how long a RAID6 rebuild takes on this device?

No one?

[millhaus]

48hrs = 63%?
Could be, remind that R6 has twice parity to restore onto new hd.

If you have 4x2TB = netto 4 TB @R6, right?

how many used data do you have?

Is your QNAP in the meantime active/accessible? Do you make any other IO on this device except rebuilding?

Check on the performance-graph for CPU, and - if possible - via ssh machine to check iostat

[forkless]

By default the RAID rebuild throughput is set very conservatively to ensure some performance while being in 'production'. Check out the thread below to give your rebuild a good boost (depending on configuration/machine it can boost your rebuild performance 500-600%)

viewtopic.php?f=11&t=10268

[insanity]

3.7TB available, 1TB used.

During rebuild, CPU was averaging around 60-80% usage.

Some network activity (NFS mounts, etc) was ongoing during re-build, but not excessive... and certainly not enough to cause a 3.5day rebuild... ?

[schumaku]

The 1.2 GHz CPU in the TS-412 is not a Formula One engine - so the time makes perfect sense, especially when there is some additional traffic aside of the pure rebuild.

[xyspider]

That seem about right to me.
Marvell 6281 1.2GHz with 256MB Ram.

My suggestion that you may avoid to do raid 6 on this one due to not enough horse power. Better get a Intel model with 2GB Ram or should go with RAID 10 which does not require lots of CPU cycle. (Still allow to fail 2 drives but the down side is odd position).

[insanity]

That seem about right to me.
Marvell 6281 1.2GHz with 256MB Ram.

My suggestion that you may avoid to do raid 6 on this one due to not enough horse power. Better get a Intel model with 2GB Ram or should go with RAID 10 which does not require lots of CPU cycle. (Still allow to fail 2 drives but the down side is odd position).

Hmph. I may upgrade to a 600 unit then...

Thanks.