{"push_id":696232406,"size":1,"distinct_size":1,"ref":"refs/heads/master","head":"c431ae0e9b10fe4759a9a5a0bcf7ff5bee8abb07","before":"4e11c0312119d7d7170d0eff82be228d6528a379","commits":[{"sha":"c431ae0e9b10fe4759a9a5a0bcf7ff5bee8abb07","author":{"email":"5db23874f34e45d59c69d81cd72d048d558566d7@gmail.com","name":"anarkia1976"},"message":"block: Make CFQ default to IOPS mode on SSDs\n\nCFQ idling causes reduced IOPS throughput on non-rotational disks.\nSince disk head seeking is not applicable to SSDs, it doesn't really\nhelp performance by anticipating future near-by IO requests.\n\nBy turning off idling (and switching to IOPS mode), we allow other\nprocesses to dispatch IO requests down to the driver and so increase IO\nthroughput.\n\nFollowing FIO benchmark results were taken on a cloud SSD offering with\nidling on and off:\n\nIdling iops avg-lat(ms) stddev bw\n------------------------------------------------------\nOn 7054 90.107 38.697 28217KB/s\nOff 29255 21.836 11.730 117022KB/s\n\nfio --name=temp --size=100G --time_based --ioengine=libaio \\\n--randrepeat=0 --direct=1 --invalidate=1 --verify=0 \\\n--verify_fatal=0 --rw=randread --blocksize=4k --group_reporting=1 \\\n--filename=/dev/sdb --runtime=10 --iodepth=64 --numjobs=10\n\nAnd the following is from a local SSD run:\n\nIdling iops avg-lat(ms) stddev bw\n------------------------------------------------------\nOn 19320 33.043 14.068 77281KB/s\nOff 21626 29.465 12.662 86507KB/s\n\nfio --name=temp --size=5G --time_based --ioengine=libaio \\\n--randrepeat=0 --direct=1 --invalidate=1 --verify=0 \\\n--verify_fatal=0 --rw=randread --blocksize=4k --group_reporting=1 \\\n--filename=/fio_data --runtime=10 --iodepth=64 --numjobs=10\n\nReviewed-by: Nauman Rafique <nauman@xxxxxxxxxx>\nSigned-off-by: Tahsin Erdogan <tahsin@xxxxxxxxxx>","distinct":true,"url":"https://api.github.com/repos/jtpoo3/kangaroo-flo/commits/c431ae0e9b10fe4759a9a5a0bcf7ff5bee8abb07"}]}