On Tue, Aug 17, 2021 at 09:25:56AM +0200, David Hildenbrand wrote: > On 17.08.21 03:37, Peter Xu wrote: > > Trace at memory_region_sync_dirty_bitmap() for log_sync() or > > global_log_sync() > > on memory regions. One trace line should suffice when it finishes, so as to > > estimate the time used for each log sync process. > > I wonder if a start/finish would be even nicer. At least it wouldn't really > result in significantly more code changes :)
Note that the "name"s I added is not only for not using start/end, it's about knowing which memory listener is slow. Start/end won't achieve that if we don't have a name for them. So far I just wanted to identify majorly kvm, vhost and kvm-smram, however it'll always be good when some log_sync is missed when tracing. I'm also wondering whether kvm-smram needs a whole bitmap as I don't know what RAM would be touched within system manager mode (as I thought it should only touch a very limited range and should be defined somewhere), but that's off-topic. If we want to make it start/end pair, I can do that too. But the 1st patch will still be wanted. Thanks, -- Peter Xu
