RAID 1 on linux, using reiserFS

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FAST install!

I went with mismatched 250 gig hard drives(one maxtor, one seagate), 7200rpm. 3 RAID partitions. All mirrored(RAID 1). one at 5 gigs for the operating system (root). 240 for the /home (documents/programs) for you windows folks) and 5 gigs for the swap area. 56 megs were left over on each drive. I did that so that sizes were perfectly identical.

Fiddling with RAID wasnt complicated, but took me some time. I had to backtrack. Configuration is still ongoing, but it looks really fast.

I'll list my drive write speed here from before, and a comparison. Both RAID 1 and reiserFS are supposed to be faster than singular drives with ext3.

Before:

2022mb in 2 seconds or 1011 MBs per second to the drive cache.

172 MB in 3.03 sec or 56.73 MB per second to the disk itself.

After

1796 MB in 2.00 seconds or 898.19 MB/sec for cache

260 MB in 3.00 sec or 86.57 MB for the disk

Results are nebulous. I didnt expect the cache to be faster, and several tests shows it varies a lot. Writes directly to the drive are faster by a good margin, but it may be because the reiserFS is quicker.

Unfortunately the method of testing tests the physical drives separately. I need to find a new way to test them as a unit.

I'm sure there's plenty of RAID testing tools out there, just not sure if they cover RAID 1. Most of the levels I see are 5, and sometimes 2...but that's Server OS's...

RAID 0 or striped seems the most common to me. Its interesting to note that what we are calling RAID on a personal use machine isnt really RAID in the sense that its not performed by a specialized and expensive card. In linux Mobo supported raid is called 'fakeRAID'. As well, the debian based systems are good at emulated or software RAID, which is what I am messing with.

I chose RAID 1 because i am not doing computationally sophisticated things, such as gaming. RAID 0 would be able to read one file from several points, speeding things up. RAID 0 can read several files at once. This was more in line with what I would find handy; I tend to have a bunch of apps open at once.

The problem with RAID 0 is that if one drive fails, your data is screwed. I'd feel ok with that on a gaming rig, but not for intellectual stuff. RAID 1 has a back up.

I dunno...the RAID systems I worked on were SCSI RAID servers, Proliants, Prosignias, etc.

R in Raid stands for Redundant. Makes ya wonder if one drive goes out, and your data is gone, then where does the redundancy come from?...

Yeah, thats true, but striped array drives are lumped in with true RAID anyway.

That's technology for ya...

Eventually, I suppose, they'll come up with a better name for what you're talking about...

I tend to just burn early and often to CD/DVD-R. I use a special, proprietary 'oh I forgot I already downloaded that/oh, I forgot I already backed that up' regimen...