Hello On a Xen/i386 I observe the kernel gets a lot of device tiemouts on SATA disks:
wd1a: device timeout reading fsbn 460630240 of 460630240-460630271 (wd1 bn 460630303; cn 456974 tn 8 sn 7), retrying ahcisata0 port 3: device present, speed: 3.0Gb/s wd1: soft error (corrected) That impacts performances alot since no I/O can happen during such an event. Here is the relevant dmesg stuff: ahcisata0 at pci0 dev 31 function 2: vendor 0x8086 product 0x1d02 (rev. 0x06) ahcisata0: interrupting at ioapic0 pin 18, event channel 5 ahcisata0: AHCI revision 1.30, 6 ports, 32 slots, CAP 0xe730ff45<EMS,PSC,SSC,PMD,ISS=0x3=Gen3,SCLO,SAL,SALP,SSNTF,SNCQ,S64A> atabus0 at ahcisata0 channel 0 (...) ahcisata0 port 3: device present, speed: 3.0Gb/s (...) wd1 at atabus3 drive 0 wd1: <WDC WD5000AADS-00S9B0> wd1: drive supports 16-sector PIO transfers, LBA48 addressing wd1: 465 GB, 969021 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 sectors wd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133) wd1(ahcisata0:3:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133) (using DMA) If the BIOS is configured without AHCI, the disk was handled by the piixide driver and it had similar troubles: piixide0:1:0: lost interrupt type: ata tc_bcount: 512 tc_skip: 0 piixide0:1:0: intr with DRQ (st=0x58) wd1a: device timeout writing fsbn 606429632 of 606429632-606429663 (wd1 bn 606429695; cn 601616 tn 12 sn 11), retrying wd1: soft error (corrected) The disk itslef has been changed multiple times without improvement. The machine has been swapped for a similar model, hence a specific hardware fault seems unlikely. And the oddest point: logs show the problem appears on january 25th 2016. Logs between september 22nd 2015 and that date show no problems. Does it rings a bell to anyone? -- Emmanuel Dreyfus m...@netbsd.org