[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 1/1] block: add cache mode with direct IO and wi
From: |
Kevin Wolf |
Subject: |
Re: [Qemu-devel] [PATCH 1/1] block: add cache mode with direct IO and without flushes |
Date: |
Thu, 15 Sep 2016 18:09:07 +0200 |
User-agent: |
Mutt/1.5.21 (2010-09-15) |
Am 15.09.2016 um 15:19 hat Denis V. Lunev geschrieben:
> This mode could be very useful for flush bottlenecks evaluation and for
> running non-persistent VMs, when host crash is considered not fatal.
>
> Signed-off-by: Denis V. Lunev <address@hidden>
> CC: Kevin Wolf <address@hidden>
> CC: Max Reitz <address@hidden>
Why not just specify the individual options?
-drive file=...,cache.direct=on,cache.no-flush=on
Kevin
> block.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/block.c b/block.c
> index 30d64e6..877165c 100644
> --- a/block.c
> +++ b/block.c
> @@ -641,6 +641,9 @@ int bdrv_parse_cache_mode(const char *mode, int *flags,
> bool *writethrough)
> if (!strcmp(mode, "off") || !strcmp(mode, "none")) {
> *writethrough = false;
> *flags |= BDRV_O_NOCACHE;
> + } else if (!strcmp(mode, "none-unsafe") || !strcmp(mode, "off-unsafe")) {
> + *writethrough = false;
> + *flags |= BDRV_O_NOCACHE | BDRV_O_NO_FLUSH;
> } else if (!strcmp(mode, "directsync")) {
> *writethrough = true;
> *flags |= BDRV_O_NOCACHE;
> --
> 2.5.0
>