zfs/cmd
Alexander Motin 026fe79646 Speculative prefetch for reordered requests
Before this change speculative prefetcher was able to detect a stream
only if all of its accesses are perfectly sequential.  It was easy to
implement and is perfectly fine for single-threaded applications.
Unfortunately multi-threaded network servers, such as iSCSI, SMB or
NFS usually have plenty of threads and may often reorder requests,
preventing successful speculation and prefetch.

This change allows speculative prefetcher to detect streams even if
requests are reordered by introducing a list of 9 non-contiguous
ranges up to 16MB ahead of current stream position and filling the
gaps as more requests arrive.  It also allows stream to proceed
even with holes up to a certain configurable threshold (25%).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #16022
2024-04-19 10:13:38 -07:00
..
raidz_test Fix multiplication converted to larger type 2022-10-28 09:30:37 -07:00
zdb zdb: Fix false leak report for BRT objects 2024-02-12 17:03:17 -08:00
zed Add Ntfy notification support to ZED 2024-02-12 14:32:11 -08:00
zfs zfs list: add '-t fs' and '-t vol' options (#15883) 2024-02-12 14:04:27 -08:00
zinject Fix unsafe string operations 2022-09-27 16:47:24 -07:00
zpool Add 'zpool status -e' flag to see unhealthy vdevs 2024-02-08 15:22:16 -08:00
zpool_influxdb Do not report bytes skipped by scan as issued. 2023-06-30 08:47:13 -07:00
zstream Reject streams that set ->drr_payloadlen to unreasonably large values 2023-01-23 13:16:22 -08:00
Makefile.am Add zilstat script to report zil kstats in a user friendly manner 2022-09-02 13:24:07 -07:00
arc_summary Speculative prefetch for reordered requests 2024-04-19 10:13:38 -07:00
arcstat.in Update arc_summary and arcstat outputs 2023-01-05 09:29:13 -08:00
dbufstat.in Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
fsck.zfs.in cmd: move single-file binaries up, extract udev programs to udev/ 2022-05-10 10:20:34 -07:00
mount_zfs.c nvpair: Constify string functions 2023-03-14 15:25:50 -07:00
zfs_ids_to_path.c Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zgenhostid.c Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zhack.c Allow zhack label repair to restore detached devices. 2023-05-03 09:03:57 -07:00
zilstat.in zil: Add some more statistics. 2023-05-25 13:51:53 -07:00
ztest.c Invoke zdb by guid to avoid import errors 2023-09-28 14:28:21 -07:00
zvol_wait zvol_wait logic may terminate prematurely 2022-10-11 12:12:04 -07:00