Bug 228464

Summary:	vfs.zfs.vdev.max_pending - does not exist anymore
Product:	Documentation	Reporter:	Slawomir Wojciech Wojtczak <vermaden>
Component:	Books & Articles	Assignee:	freebsd-doc (Nobody) <doc>
Status:	Closed Overcome By Events
Severity:	Affects Only Me	CC:	smh
Priority:	---
Version:	Latest
Hardware:	Any
OS:	Any

Description Slawomir Wojciech Wojtczak 2018-05-24 16:59:12 UTC

https://www.freebsd.org/doc/handbook/zfs-advanced.html

Documentation states:

vfs.zfs.vdev.max_pending - Limit the number of pending I/O requests per device. A higher value will keep the device command queue full and may give higher throughput. A lower value will reduce latency. This value can be adjusted at any time with sysctl(8).

But vfs.zfs.vdev.max_pending does not exist anymore.
% sysctl vfs.zfs.vdev.max_pending
sysctl: unknown oid 'vfs.zfs.vdev.max_pending'

% uname -srnm
FreeBSD t420s.local 11.2-BETA2 amd64

Comment 1 Steven Hartland freebsd_committer

2018-05-24 17:09:00 UTC

Looks like this is just old, replaced by the new type based scheduling.
sysctl -a | grep vdev | grep active 
vfs.zfs.vdev.trim_max_active: 64
vfs.zfs.vdev.trim_min_active: 1
vfs.zfs.vdev.scrub_max_active: 2
vfs.zfs.vdev.scrub_min_active: 1
vfs.zfs.vdev.async_write_max_active: 10
vfs.zfs.vdev.async_write_min_active: 1
vfs.zfs.vdev.async_read_max_active: 3
vfs.zfs.vdev.async_read_min_active: 1
vfs.zfs.vdev.sync_write_max_active: 10
vfs.zfs.vdev.sync_write_min_active: 10
vfs.zfs.vdev.sync_read_max_active: 10
vfs.zfs.vdev.sync_read_min_active: 10
vfs.zfs.vdev.max_active: 1000
vfs.zfs.vdev.async_write_active_max_dirty_percent: 60
vfs.zfs.vdev.async_write_active_min_dirty_percent: 30