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Subject: Re: Boot partition size
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From: Jan Bramkamp <crest@rlwinm.de>
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Date: Thu, 9 Feb 2017 12:14:12 +0100
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On 29/01/2017 06:43, Aristedes Maniatis wrote:
> On 29/1/17 3:50pm, Warner Losh wrote:
>>  (2) shrinking a swap partition to snag
>> some space
> Yes, except I put my swap into a zvol. I did this when I lost a disk once with a dedicated swap partition and that caused the system to crash. So I realised that dedicated swap was a really bad idea and I needed to choose between zvol and gmirror. I chose zvol to avoid having one more thing to check and worry about.

Swapping to ZVOLs is dangerous. Writes to a ZVOL may require kernel 
memory allocations to finish. This can deadlock/panic your system if the 
write was to a swap device. I would recommend using GEOM mirror for swap 
devices.