[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [PATCH v3 3/9] block/block-copy: specialcase first copy_range reques
From: |
Max Reitz |
Subject: |
Re: [PATCH v3 3/9] block/block-copy: specialcase first copy_range request |
Date: |
Tue, 10 Mar 2020 14:42:18 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 |
On 06.03.20 08:38, Vladimir Sementsov-Ogievskiy wrote:
> In block_copy_do_copy we fallback to read+write if copy_range failed.
> In this case copy_size is larger than defined for buffered IO, and
> there is corresponding commit. Still, backup copies data cluster by
> cluster, and most of requests are limited to one cluster anyway, so the
> only source of this one bad-limited request is copy-before-write
> operation.
>
> Further patch will move backup to use block_copy directly, than for
> cases where copy_range is not supported, first request will be
> oversized in each backup. It's not good, let's change it now.
>
> Fix is simple: just limit first copy_range request like buffer-based
> request. If it succeed, set larger copy_range limit.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
> Reviewed-by: Andrey Shinkevich <address@hidden>
> ---
> block/block-copy.c | 41 +++++++++++++++++++++++++++++++----------
> 1 file changed, 31 insertions(+), 10 deletions(-)
Reviewed-by: Max Reitz <address@hidden>
signature.asc
Description: OpenPGP digital signature
[PATCH v3 6/9] block/block-copy: refactor interfaces to use bytes instead of end, Vladimir Sementsov-Ogievskiy, 2020/03/06
[PATCH v3 2/9] block/block-copy: fix progress calculation, Vladimir Sementsov-Ogievskiy, 2020/03/06
[PATCH v3 9/9] block/block-copy: hide structure definitions, Vladimir Sementsov-Ogievskiy, 2020/03/06