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Reply-To: lev@FreeBSD.org
Subject: Re: ZFS L2ARC checksum errors after compression
References: <921575537.20161029143626@serebryakov.spb.ru>
 <3dae7691-fcd1-b3b9-445c-b81d6f0cdc52@FreeBSD.org>
To: Andriy Gapon <avg@FreeBSD.org>, freebsd-fs <freebsd-fs@FreeBSD.org>
From: Lev Serebryakov <lev@FreeBSD.org>
Organization: FreeBSD
Message-ID: <fe4962d6-75c3-32c0-8d28-c99661e5161f@FreeBSD.org>
Date: Thu, 3 Nov 2016 22:43:07 +0300
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On 29.10.2016 16:32, Andriy Gapon wrote:

 Looks like L2ARC is unusable now if your have compression enabled on
FSes. It shows 2x compression (ALLOC = 2xSIZE), and tons of checksum
errors. I simply don't have compressible enough data on my FSes! It is
mostly media files! Looks like this data is bogus.

> I think that a recent upstream change, compressed ARC support, reintroduced an a
> old problem that was fixed a while ago.

-- 
// Lev Serebryakov