On Thu, Aug 27, 2020 at 07:18:07PM +0000, Dmitry Fomichev wrote: > > > > -----Original Message----- > > From: Alexey Dobriyan <adobriyan@xxxxxxxxx> > > Sent: Friday, August 21, 2020 1:07 PM > > To: Dmitry Fomichev <Dmitry.Fomichev@xxxxxxx> > > Cc: fio@xxxxxxxxxxxxxxx > > Subject: Re: [PATCH] zbd: remove reset_zone flag from fio_zone_info > > > > On Wed, Aug 19, 2020 at 07:35:03PM +0000, Dmitry Fomichev wrote: > > > > > > > > > > -----Original Message----- > > > > From: Alexey Dobriyan <adobriyan@xxxxxxxxx> > > > > Sent: Wednesday, August 19, 2020 8:56 AM > > > > To: Dmitry Fomichev <Dmitry.Fomichev@xxxxxxx> > > > > Cc: fio@xxxxxxxxxxxxxxx > > > > Subject: Re: [PATCH] zbd: remove reset_zone flag from fio_zone_info > > > > > > > > > The reset_zone flag that is defined in fio_zone_info structure is > > > > > only referenced in zbd_adjust_block() function. Convert this flag > > > > > to a local variable and save some room in zbd_info array which can > > > > > be pretty large when running fio against high capacity zoned devices. > > > > > > > > This flag should be kept. > > > > > > > > Test can crash or be interrupted leaving hw in indeterminate state, > > > > it must be restarted from clean state. Or test can be precondition and > > > > zone should not be reset. > > > > > > This is beyond the scope of fio. Any preconditioning of zones is done > > > by external scripts that have no access to this flag. Tools like blkzone, > > > libzbc or nvme-cli are typically used to precondition zones before > > > testing and to analyze zone state after test runs. > > > > If it is a matter of policy that fio doesn't do preconditioning, > > then the patch is OK. > > > > We do preconditioning in fio, it is neat: > > * don't need external programs > > * everything inside one job file > > * not a lot of code to add > > > > But to do this, flag must live in "struct fio_zone_info". > > > > [zra] > > zone_reset_all=1 > > The way I understand this, this option makes ZBD code to set the reset_zone > flag for all zones during init. This will force zone reset before the first write > to a zone. This indeed is a neat idea and this feature looks to be pretty > lightweight as you said. > > > zone_finish_all=1 > > How does this option work? Seems like you have added a new > finish_zone flag and you finish every zone for which the flag is set > instead of performing the first write to the zone... Sorry for delay. ZRA marks every zone in [->min_zone, ->max_zone) for reset, forcing Zone Reset before first write. ZFA sends Finish Zone with "all" flag set synchronously. Some job orchestration is required but once it is done, jobs run reliably. > > rw=write > > > > [pre] > > stonewall > > zone_reset_all=0 > > zone_finish_all=0 > > job_max_open_zones=... > > rw=write > > ... > > > > [j] > > stonewall > > zone_reset_all=0 > > zone_finish_all=0 > > rw=randread > > ... > > I guess we can hold off with removing the reset_zone flag if you are planning > to send the patch for this. Thanks, I'll try to extract something mainlineable.
