Hello, On Tue, Jan 03, 2023 at 02:19:17PM +0900, Damien Le Moal wrote: > Finally, patch 7 enables FUA support by default in libata for devices > supporting this features. These optional features tend to be broken in various and subtle ways, especially the ones which don't show clear and notable advantages and thus don't get used by everybody. I'm not necessarily against enabling it by default but we should have better justifications as we might unnecessarily cause a bunch of painful and subtle failures which can take a while to sort out. * Can the advantages of using FUA be demonstrated in a realistic way? IOW, are there workloads which clearly benefit from FUA? My memory is hazy but we only really use FUA from flush sequence to turn flush, write, flush sequence into flush, FUA-write. As all the heavy lifting is done in the first flush anyway, I couldn't find a case where that optimization made a meaningful difference but I didn't look very hard. * Do we know how widely FUA is used now? IOW, is windows using FUA by default now? If so, do we know whether they have a blocklist? Thanks. -- tejun
