[Qemu-devel] Switch to thread pool from posix-aio

[Qemu-devel] Switch to thread pool from posix-aio

[Anthony Liguori]

I've just committed the thread pool patch I posted a few days ago (plus 
the suggested cleanups).

Please test this especially if you're using a very old glibc or a 
non-Linux Unix.  Also pay attention for any performance differences.  I 
don't think any will be noticable unless you're doing very heavy IO and 
I expect it will only improve things.

If in the past you've been forced to use --disable-aio, please try again 
without --disable-aio and let me know if it now works.

Regards,

Anthony Liguori

Re: [Qemu-devel] Switch to thread pool from posix-aio

[Blue Swirl]

On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
> I've just committed the thread pool patch I posted a few days ago (plus the
> suggested cleanups).
>
>  Please test this especially if you're using a very old glibc or a non-Linux
> Unix.  Also pay attention for any performance differences.  I don't think
> any will be noticable unless you're doing very heavy IO and I expect it will
> only improve things.

Compilation is broken on Debian stable, you need librt for
timer_create, clock_gettime etc.

Re: [Qemu-devel] Switch to thread pool from posix-aio

[Anthony Liguori]

Blue Swirl wrote:
> On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
>   
>> I've just committed the thread pool patch I posted a few days ago (plus the
>> suggested cleanups).
>>
>>  Please test this especially if you're using a very old glibc or a non-Linux
>> Unix.  Also pay attention for any performance differences.  I don't think
>> any will be noticable unless you're doing very heavy IO and I expect it will
>> only improve things.
>>     
>
> Compilation is broken on Debian stable, you need librt for
> timer_create, clock_gettime etc.
>   

I'll add a proper configure test for that.  I guess that means that 
--disable-aio was broken on Debian unstable too.

Regards,

Anthony Liguori

Re: [Qemu-devel] Switch to thread pool from posix-aio

[Anthony Liguori]

[-- Attachment #1: Type: text/plain, Size: 625 bytes --]

Blue Swirl wrote:
> On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
>   
>> I've just committed the thread pool patch I posted a few days ago (plus the
>> suggested cleanups).
>>
>>  Please test this especially if you're using a very old glibc or a non-Linux
>> Unix.  Also pay attention for any performance differences.  I don't think
>> any will be noticable unless you're doing very heavy IO and I expect it will
>> only improve things.
>>     
>
> Compilation is broken on Debian stable, you need librt for
> timer_create, clock_gettime etc.
>   

Does this patch fix your problem?

Regards,

Anthony Liguori

[-- Attachment #2: rt-configure.patch --]
[-- Type: text/x-patch, Size: 779 bytes --]

diff --git a/configure b/configure
index d1f0c04..e997a32 100755
--- a/configure
+++ b/configure
@@ -972,6 +972,26 @@ if [ -x "`which texi2html 2>/dev/null`" ] && \
   build_docs="yes"
 fi
 
+##########################################
+# Do we need librt
+cat > $TMPC <<EOF
+#include <signal.h>
+#include <time.h>
+int main(void) { clockid_t id; return clock_gettime(id, NULL); }
+EOF
+
+rt=no
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
+  :
+elif $cc $ARCH_CFLAGS -o $TMPE $TMPC -lrt 2> /dev/null ; then
+  rt=yes
+fi
+
+if test "$rt" = "yes" ; then
+  # Hack, we should have a general purpose LIBS for this sort of thing
+  AIOLIBS="$AIOLIBS -lrt"
+fi
+
 if test "$mingw32" = "yes" ; then
   if test -z "$prefix" ; then
       prefix="c:\\\\Program Files\\\\Qemu"

Re: [Qemu-devel] Switch to thread pool from posix-aio

[Blue Swirl]

On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
> Blue Swirl wrote:
>
> > On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
> >
> >
> > > I've just committed the thread pool patch I posted a few days ago (plus
> the
> > > suggested cleanups).
> > >
> > >  Please test this especially if you're using a very old glibc or a
> non-Linux
> > > Unix.  Also pay attention for any performance differences.  I don't
> think
> > > any will be noticable unless you're doing very heavy IO and I expect it
> will
> > > only improve things.
> > >
> > >
> >
> > Compilation is broken on Debian stable, you need librt for
> > timer_create, clock_gettime etc.
> >
> >
>
>  Does this patch fix your problem?

Yes, it does.

Re: [Qemu-devel] Switch to thread pool from posix-aio

[Anthony Liguori]

Blue Swirl wrote:
> On 12/12/08, Anthony Liguori <anthony@codemonkey.ws> wrote:
>   
>>
>
> Yes, it does.
>   

Thanks.  I committed a work-around to get the build going again.  I'll 
try to do a proper cleanup soon.

Regards,

Anthony Liguori