Commits on Jun 10, 2020

1. vfs: Add vfs.Prefetch, use it for reading ahead data blocks …

   For sequential-like IO workload where we read
   data blocks one after the other in quick succession,
   signalling the OS to asynchronously bring them to
   cache in advance can deliver significant savings in IOPS
   dispatched. In IOPS-bound workloads such as backup on
   an EBS disk, this delivers a 3x speedup. Presumably
   aggregate queries and compactions will be faster
   as well, though this hasn't been benchmarked in
   practice yet.
   
   This change maintains a counter for the number of data
   block reads performed in a singleLevelIterator, and
   when that count exceeds 2, a readahead system
   call is made on Linux. RocksDB has almost
   the exact same behaviour, including the same
   min/max readahead sizes and read count thresholds.
   
   Will address cockroachdb/cockroach#49710
   when it lands in cockraoch.

   

   itsbilal committed Jun 10, 2020
   Configuration menu

   • View commit details
   • Copy full SHA for 9d9346e
   • Browse repository at this point

   Copy the full SHA

   9d9346e View commit details

   Browse the repository at this point in the history