linux - slow software raid

I've got software raid 1 for / and /home and it seems I'm not getting the right speed out of it.

Reading from md0 I get around 100 MB/sec
Reading from sda or sdb I get around 95-105 MB/sec

I thought I would get more speed (while reading data) from two drives. I don't know what is the problem.

I'm using kernel 2.6.31-18

hdparm -tT /dev/md0

/dev/md0: Timing cached reads: 2078
MB in 2.00 seconds = 1039.72 MB/sec
Timing buffered disk reads: 304 MB in
3.01 seconds = 100.96 MB/sec

hdparm -tT /dev/sda

/dev/sda: Timing cached reads: 2084
MB in 2.00 seconds = 1041.93 MB/sec

Timing buffered disk reads: 316 MB in
3.02 seconds = 104.77 MB/sec

hdparm -tT /dev/sdb

/dev/sdb: Timing cached reads: 2150
MB in 2.00 seconds = 1075.94 MB/sec
Timing buffered disk reads: 302 MB in
3.01 seconds = 100.47 MB/sec

Edit:
Raid 1

Answer

Take a look at the following article at nixCraf, HowTo: Speed Up Linux Software Raid Building And Re-syncing.

It explains the different settings in /proc that can be adjusted to influence the software raid speed. (Not just during building/syncing as the title suggests.)

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