From: Peter Amstutz Date: Wed, 30 Mar 2022 02:13:45 +0000 (-0400) Subject: 18941: clamp prefetch to 6 X-Git-Tag: 2.4.0~20^2~4 X-Git-Url: https://git.arvados.org/arvados.git/commitdiff_plain/33e4f1574f5bd14784c65863739478ff864732d2 18941: clamp prefetch to 6 Arvados-DCO-1.1-Signed-off-by: Peter Amstutz --- diff --git a/services/fuse/arvados_fuse/fusedir.py b/services/fuse/arvados_fuse/fusedir.py index bfd06c714e..876825a370 100644 --- a/services/fuse/arvados_fuse/fusedir.py +++ b/services/fuse/arvados_fuse/fusedir.py @@ -525,8 +525,9 @@ class CollectionDirectory(CollectionDirectoryBase): self.collection.update() new_collection_record = self.collection.api_response() else: - # experimentally, 4 block prefetch seems to be optimal. - get_threads = min(max((self.api.keep.block_cache.cache_max // (64 * 1024 * 1024)) - 1, 1), 4) + # too much prefetch and you end up stepping on your own transfers + # experimentally the optimal somewhere between 4 and 6 + get_threads = min(max((self.api.keep.block_cache.cache_max // (64 * 1024 * 1024)) - 1, 1), 6) # Create a new collection object if uuid_pattern.match(self.collection_locator): coll_reader = arvados.collection.Collection(