mirror_zfs/man/man8/zpool-prefetch.8
Allan Jude 62e7d3c89e
ddt: add support for prefetching tables into the ARC
This change adds a new `zpool prefetch -t ddt $pool` command which
causes a pool's DDT to be loaded into the ARC. The primary goal is to
remove the need to "warm" a pool's cache before deduplication stops
slowing write performance. It may also provide a way to reload portions
of a DDT if they have been flushed due to inactivity.

Sponsored-by: iXsystems, Inc.
Sponsored-by: Catalogics, Inc.
Sponsored-by: Klara, Inc.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Will Andrews <will.andrews@klarasystems.com>
Signed-off-by: Fred Weigel <fred.weigel@klarasystems.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Don Brady <don.brady@klarasystems.com>
Co-authored-by: Will Andrews <will.andrews@klarasystems.com>
Co-authored-by: Don Brady <don.brady@klarasystems.com>
Closes #15890
2024-07-26 09:16:18 -07:00

47 lines
1.3 KiB
Groff

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.\" Copyright (c) 2023, Klara Inc.
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.Dd February 14, 2024
.Dt ZPOOL-PREFETCH 8
.Os
.
.Sh NAME
.Nm zpool-prefetch
.Nd Loads specific types of data for the given pool
.Sh SYNOPSIS
.Nm zpool
.Cm prefetch
.Fl t Ar type
.Ar pool
.Sh DESCRIPTION
.Bl -tag -width Ds
.It Xo
.Nm zpool
.Cm prefetch
.Fl t Li ddt
.Ar pool
.Xc
Prefetch data of a specific type for the given pool; specifically the DDT,
which will improve write I/O performance when the DDT is resident in the ARC.
.El