diff options
| author | Christoph Hellwig <hch@lst.de> | 2009-08-20 16:58:35 +0200 |
|---|---|---|
| committer | Anthony Liguori <aliguori@us.ibm.com> | 2009-08-27 20:30:22 -0500 |
| commit | 5c6c3a6c54b23caa84fb4e046e85a461612279bb (patch) | |
| tree | 7c23c2c86ca96f0a1b3dcbb86c70d5989e156710 /qemu-options.hx | |
| parent | 9ef91a677110ec200d7b2904fc4bcae5a77329ad (diff) | |
raw-posix: add Linux native AIO support
Now that do have a nicer interface to work against we can add Linux native
AIO support. It's an extremly thing layer just setting up an iocb for
the io_submit system call in the submission path, and registering an
eventfd with the qemu poll handler to do complete the iocbs directly
from there.
This started out based on Anthony's earlier AIO patch, but after
estimated 42,000 rewrites and just as many build system changes
there's not much left of it.
To enable native kernel aio use the aio=native sub-command on the
drive command line. I have also added an option to qemu-io to
test the aio support without needing a guest.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'qemu-options.hx')
| -rw-r--r-- | qemu-options.hx | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/qemu-options.hx b/qemu-options.hx index e3bd314509..0c2b310562 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -95,7 +95,7 @@ DEF("drive", HAS_ARG, QEMU_OPTION_drive, "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" " [,cache=writethrough|writeback|none][,format=f][,serial=s]\n" - " [,addr=A][,id=name]\n" + " [,addr=A][,id=name][,aio=threads|native]\n" " use 'file' as a drive image\n") DEF("set", HAS_ARG, QEMU_OPTION_set, "-set group.id.arg=value\n" @@ -128,6 +128,8 @@ These options have the same definition as they have in @option{-hdachs}. @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}). @item cache=@var{cache} @var{cache} is "none", "writeback", or "writethrough" and controls how the host cache is used to access block data. +@item aio=@var{aio} +@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. @item format=@var{format} Specify which disk @var{format} will be used rather than detecting the format. Can be used to specifiy format=raw to avoid interpreting |