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Subject: Re: TRIM, iSCSI and %busy waves
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From: "Eugene M. Zheganin" <eugene@zhegan.in>
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Date: Thu, 5 Apr 2018 20:15:45 +0500
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Hello,

On 05.04.2018 19:57, Steven Hartland wrote:
> You can indeed tune things here are the relevant sysctls:
> sysctl -a | grep trim |grep -v kstat
> vfs.zfs.trim.max_interval: 1
> vfs.zfs.trim.timeout: 30
> vfs.zfs.trim.txg_delay: 32
> vfs.zfs.trim.enabled: 1
> vfs.zfs.vdev.trim_max_pending: 10000
> vfs.zfs.vdev.trim_max_active: 64
> vfs.zfs.vdev.trim_min_active: 1
> vfs.zfs.vdev.trim_on_init: 1
>
Well, I've already seen these. How do I tune them ? The idea of just 
tampering with them and seeing what will happen doesn't look like a 
bright one to me. Do I increase or decrease them ? Which ones do I have 
to avoid ?

Eugene.