Very poor RAID write performance

I confirm this. I've been running similar tests. With two drives in
RAID-1, I get roughly 100MB/s reads and only 20MB/s writes. The
motherboard as another raid controller (SATA only) which does ~95/70
MB/s.

For Raid-0 (same two drives), I get 195MB/s reads and 185MB/s writes on
the SATA controller and only 110/88 on the LSI MegaRAID SAS 8344ELP

For fun, I also compared so software raid, where I get 110MB/s write
and 105MB/s read.

In other words, as far as I am concerned, the LSI MegaRAID SAS 8344ELP
is worst than software raid.

The other controller found the on xw9400 (NVidia I think) is fairly
decent however.