Read priority when deferred write is on.
Posted: Wed Aug 12, 2020 1:12 pm
As the title says, my suggestion would be for an option (or even it being default), to give priority to non cached read, over deferred write when deferred write is enabled.
What i mean by this, is say, i have 5 gb of deferred l1 write currently being flushed, on an hdd this can take a while. If i try to read stuff that is not currently in the cache of that same hdd, it ends up being super slow since it share the io with the write operation. The suggestion would be that when a read request is in progress, to pause the deferred writes (unless the cache is full and more write are being requested offcourse).
This would lead to a much more consistent experience performance wise when using deferred write. As it is right now, its great when i write a bunch of files to it, but then im basically stuck with subpar read performance until its done actually writing those.
What i mean by this, is say, i have 5 gb of deferred l1 write currently being flushed, on an hdd this can take a while. If i try to read stuff that is not currently in the cache of that same hdd, it ends up being super slow since it share the io with the write operation. The suggestion would be that when a read request is in progress, to pause the deferred writes (unless the cache is full and more write are being requested offcourse).
This would lead to a much more consistent experience performance wise when using deferred write. As it is right now, its great when i write a bunch of files to it, but then im basically stuck with subpar read performance until its done actually writing those.