How long time to format RAID5? (Is 70h normal?)

[nutte]

I've just configured a RAID-5 containing 3 400Gb Seagate-drives connected to the Sil3114 on my D955XCS-motherboard and made two partitions of about 380Gb each. Everything seems to be ok, but I got very confused when I woke up today and only 25% of the format was done on the first partition.

Should it really take several days to format a RAID5-set? (I estimate each partition will take about 35h)

[pointreyes]

Are you formatting or building the RAID 5? Considering you are not using a real RAID 5 controller (I'm sorry but an onboard RAID 5 using a cheap $5~$15 chip is not very convincing to me as being a good controller for RAID 5 ), I would not be surprised with building the RAID 5 array in the length of time it's taking for a large array. RAID 5 is a two step process, you assigned the drives for RAID 5 is step 1, step 2 is the array building. I think it took about 1.5 hours to build my RAID 5 array with a smaller 4 x 120GB drive array.

[nutte]

Originally Posted by pointreyes

Are you formatting or building the RAID 5? Considering you are not using a real RAID 5 controller (I'm sorry but an onboard RAID 5 using a cheap $5~$15 chip is not very convincing to me as being a good controller for RAID 5 ), I would not be surprised with building the RAID 5 array in the length of time it's taking for a large array. RAID 5 is a two step process, you assigned the drives for RAID 5 is step 1, step 2 is the array building. I think it took about 1.5 hours to build my RAID 5 array with a smaller 4 x 120GB drive array.

Formatting.
Building, or creating, the array didn't take any time at all (less than a second). But, as I said, everything looks fine.

[pointreyes]

Then 70 hours is definitely too long.

Maybe test the drives with the manufacturers diagnostic software. You might have a drive that went bellyup on ya.

[nutte]

Some additional info: (from original poster)

I canceled the formatting this morning, but have now started it again after verifying drivers and installing Silicon Image SATARAID5-program.

When looking in the Task Summary in this SATARAID5-program during the format I can read:
Task: 0
Operation: Restore Redundancy
Parameters: Raid Group 0
Status: Active
Priority: 10
Progress: 5%
Start Time: 2/20/06 11:35:35 AM
End Time:
Remaining: 33:27:42

Looks like my estimate of 35h was pretty good ;-)

Anybody know what "Restore Redundancy" means in this sense? Is it maybe creating the RAID-5 array during the format? (I did start a regular format)

[nutte]

Originally Posted by pointreyes

Then 70 hours is definitely too long.

Maybe test the drives with the manufacturers diagnostic software. You might have a drive that went bellyup on ya.

Thanks, but I've checked all three drives and they seems to be in perfect condition.

[pointreyes]

Originally Posted by nutte

Anybody know what "Restore Redundancy" means in this sense? Is it maybe creating the RAID-5 array during the format? (I did start a regular format)

Yes, that's the second step I was talking about. I suspect the restore redundancy is the parity bit building. I remember from my other RAID 5 builds that I always had to wait for the parity building which always took longer than the formating process.

[nutte]

Originally Posted by pointreyes

Yes, that's the second step I was talking about. I suspect the restore redundancy is the parity bit building. I remember from my other RAID 5 builds that I always had to wait for the parity building which always took longer than the formating process.

Ok, thanks a lot.
I assume everything is in order and that it does the format and parity bit building in one step. Since the Sil3114 is a "cheap" RAID-5 solution it probably takes a little bit longer to "prepare" than a true hardware solution.

I do however think it's pretty strange that I didn't found anybody else wondering about this when doing a quick search on internet. 70h is quite a long time and should have more people than me starting to wonder...

[auxxum]

just a suggestion - software based raid5 solutions (actually emulations of hardware (on-board cpu) based raid5 solutions) do run slow, and some software based adapter cards are slower than others...

I v. recently had lunch w/promise tw guys, talked about tx4310 raid 0/1/5software & touched on raid5 build time - using sata150 250gbx3 about 25hrs - using sata300 250gbx3 about 18hrs - this assumes fast mobo cpu and ALL other apps disabled & NO lan connection to eliminate automatic updates various apps linking for updates

70hrs seems a little long - something else may have been running in background

[nutte]

Originally Posted by auxxum

just a suggestion - software based raid5 solutions (actually emulations of hardware (on-board cpu) based raid5 solutions) do run slow, and some software based adapter cards are slower than others...

I v. recently had lunch w/promise tw guys, talked about tx4310 raid 0/1/5software & touched on raid5 build time - using sata150 250gbx3 about 25hrs - using sata300 250gbx3 about 18hrs - this assumes fast mobo cpu and ALL other apps disabled & NO lan connection to eliminate automatic updates various apps linking for updates

70hrs seems a little long - something else may have been running in background

Thanks for giving me some figures. I haven’t been able to read elsewhere if it normally takes 1h or 100, but this at least indicates that it’s not that way off.

What to you mean by “something else may have been running in background”? My CPU doesn’t work at all during the format, so I can’t see that that should make any difference at all.


Format update:
The format has failed three times, all three times at about 29%. Every time I created the RADI5-set in the bios, i.e. a legacy set. Checked and changed cables, tested drives etc in between, but nothing helped.
I’ve now made a “regular” (i.e. non-bootable) RAID5-set (in the SATARAID5-program) and everything seems to work fine so far, it’s about 3h left until the format should be finished. It might be so that it creates/formats the complete disc, i.e. both partitions, even though I only have started a format on the first partition.


Question:
Did I do the correct thing by creating one RAID5-set of the complete disc and then make 2 partitions? Would it have been any advantage, or disadvantage, to create two RAID5-sets and then make one partition each on them?

[nutte]

Another update (might help somebody):

After the "3 hours left" I mentioned in my previous post it started with the actual formatting of the drive which took another 30-40 hours. (Total of about 80h) Unbelievable!

Today the formatting (of partition 1 of 2) was finally finished and I started to test the performance. Well, total disappointment!
Write: 8Mb/s (normally single drive use about 50Mb/s)
Read: 50-60Mb/s (normally single drive use about 55Mb/s)


So, the read speed was ok, but the write-speed totally unacceptable.
Guess the slow format was due to the extremely bad write-performance.
Since I couldn’t use this I had three choices. Go out and buy a hardware RAID5-controller (preferable Areca), use as three single drives, or use the Sil3114 and go with another RAID-setup.
Since I have previously used Sil3114 on another motherboard for RAID0 with good results I wasn’t afraid of using that particular controller (although not for RAID5). I’m right now formatting a RAID1-set and use the third drive as a regular single drive. The format time of about 1.5-2h feels like a breeze.

So, conclusion: Do not use Sil3114 for RAID 5!!!

[pointreyes]

Originally Posted by nutte

So, conclusion: Do not use Sil3114 for RAID 5!!!

Yeah, I tried the Si3114 once in RAID5 and it was very dismal. I think I got 11Meg write. I have grown spoiled with my RAIDCore. 100Meg/sec+ reads and writes with a 4 disk RAID 5 is so much nicer. The Areca is a very nice controller as well and AFAIK is considered better than the RAIDCore.

[auxxum]

I answered my own question...