Thilo Herrmann wrote:
> What I´m interested in: has anyone else had any major run-time-problems
> with the software-raid (981215 or january edition)?
I've used december patches on a 5x9GB U2W SCSI RAID with great success.
Speed is excellent, stability is perfect. No complaints.
> P133, 64 MB ram, no swap (a 486 would probably do it, too)
> 4 x ibm IDE 16.8GB drives, promise controller.
> No DMA (if 2.0.36 would support it, I probably still wouldn´t use it).
2.0.36 does support UltraDMA on my workstation machine with a 6.5GB
Seagate drive and the Intel BX chipset integrated IDE. That works fine,
too. Don't know about the Promise IDE cards though.
> - CPU usage during raid rebuild is high, i.e. the system feels somewhat
> clunky (means: when holding a key for autorepeat, the cursor "jumps").
> If some other process produces constant CPU usage, the raid rebuild load
> goes down and is no more noticeable. I suppose this behaviour is due to
> simultaneous IDE-polling of four drives (which is hard for any CPU).
I think your guess is right - it see no performance degradation when the
aforementioned (admittedly quite fast) system is running background
resync. 80MB/s busmaster-DMA SCSI sure is nice. ;) (23MB/s streaming
speed in bonnie benchmarks).
When I tried PIO-mode on my workstation box, the system became "chunky"
even with the one drive doing heavy I/O. PIO puts a huge strain on the
CPU. DMA works miracles in similar circumstances.
--
osma ahvenlampi || | || | | | || | r a z o r f i s h
| | | | h e l s i n k i
