Hello, Mark. Mark Lord wrote: > Tejun Heo wrote: >> Speed down rules were too conservative. Adjust them a bit. >> >> * More than 10 timeouts can't happen in 5 minutes as command timeout >> is 30secs. Lower the limit for rule #1 to 6. >> >> * 10 timeouts is too high for rule #3 too. Lower it to 6. >> >> * SATAPI can benefit from falling back to PIO too. Allow SATAPI >> devices to fall back to PIO. > .. > > Mmmm... I see two remaining problems with this: > > -- bad sectors (media errors) will cause inappropriate speed-downs. No. Media error is category 0 error which doesn't affect speed down at all. > -- deliberate (or otherwise) errors via SG_IO will cause inappropriate > speed-downs. No, only device errors issued via block layer are considered for speed down (ATA_QCFLAG_IO). SG_IO commands will never trigger speed down unless the error is HSM or timeout. Thanks. -- tejun - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
