Re: qemu emulated machine crashes due to disk timeouts

[Jaromír Doleček <jaromir.dolecek%gmail.com@localhost>]

Le jeu. 14 mai 2020 à 15:19, <maya%netbsd.org@localhost> a écrit :
> > Bumped ATA_DELAY to 30000 (was 10000), and the VM stayed up overnight,
> > only logging the one correctable soft error:
> >
> > May  7 04:19:29 qemu /netbsd: [ 16290.3345912] autoconfiguration error: piixide0:0:0: lost interrupt
> > May  7 04:19:29 qemu /netbsd: [ 16290.3345912]  type: ata tc_bcount: 512 tc_skip: 0
> > May  7 04:19:29 qemu /netbsd: [ 16290.3345912] autoconfiguration error: piixide0:0:0: bus-master DMA error: missing interrupt, status=0x21
> > May  7 04:19:29 qemu /netbsd: [ 16290.6088515] wd0a: DMA error writing fsbn 1801813 (wd0 bn 1801876; cn 879 tn 52 sn 20), xfer 38, retry 0
> > May  7 04:19:29 qemu /netbsd: [ 16292.6053372] wd0: soft error (corrected) xfer 38
> >
> > Would making ATA_DELAY configurable via options(4) be worth it?
>
> QEMU emulation isn't a niche setup, we should aim to have it work out of
> the box without adjusting sysctls, IMO.

I agree. Let's fix QEMU IDE emulation?

Seriously though I think that it wouldn't hurt to just bump ATA_DELAY
to 30 seconds by default.

Also as another general suggestion - you'll generally get more
performance by using the PV drivers i.e. virtio, or ahcisata
emulation.

Jaromir