Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Am 16.02.2015 um 16:41 schrieb Stefan Priebe - Profihost AG: Am 16.02.2015 um 15:49 schrieb Paolo Bonzini pbonz...@redhat.com: On 16/02/2015 15:47, Stefan Priebe - Profihost AG wrote: Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). If I do not enable-debug dh_strip does not extract any debugging symbols. Maybe you forgot --disable-strip? Regards, Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Jennifer Guild, Dilip Upmanyu, Graham Norton; HRB 21284 (AG Nürnberg)
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
On 16/02/2015 16:41, Stefan Priebe - Profihost AG wrote: Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). If I do not enable-debug dh_strip does not extract any debugging symbols. Then you need --disable-strip too. Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Am 16.02.2015 um 16:50 schrieb Andreas Färber: Am 16.02.2015 um 16:41 schrieb Stefan Priebe - Profihost AG: Am 16.02.2015 um 15:49 schrieb Paolo Bonzini pbonz...@redhat.com: On 16/02/2015 15:47, Stefan Priebe - Profihost AG wrote: Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). If I do not enable-debug dh_strip does not extract any debugging symbols. Maybe you forgot --disable-strip? Thanks! Stefan Regards, Andreas
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Am 16.02.2015 um 16:49 schrieb Paolo Bonzini: On 16/02/2015 16:41, Stefan Priebe - Profihost AG wrote: Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). If I do not enable-debug dh_strip does not extract any debugging symbols. Then you need --disable-strip too. Thanks! Stefan Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Hi, Am 16.02.2015 um 13:24 schrieb Paolo Bonzini: On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Paolo Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Stefan
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
On 16/02/2015 15:43, Stefan Priebe - Profihost AG wrote: Hi, Am 16.02.2015 um 13:24 schrieb Paolo Bonzini: On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
On Mon, Feb 16, 2015 at 5:47 PM, Stefan Priebe - Profihost AG s.pri...@profihost.ag wrote: Hi, Am 16.02.2015 um 15:44 schrieb Paolo Bonzini: On 16/02/2015 15:43, Stefan Priebe - Profihost AG wrote: Hi, Am 16.02.2015 um 13:24 schrieb Paolo Bonzini: On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Hi Stefan, splitdebug will help you there. Also this is a standard way to ship debugging symbols in most distribuitions, so I wonder if you may use just a generic build skeleton for this task...
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Hi, Am 16.02.2015 um 15:44 schrieb Paolo Bonzini: On 16/02/2015 15:43, Stefan Priebe - Profihost AG wrote: Hi, Am 16.02.2015 um 13:24 schrieb Paolo Bonzini: On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Greets, Stefan
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
On 16/02/2015 15:47, Stefan Priebe - Profihost AG wrote: Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Hi, Am 16.02.2015 um 15:58 schrieb Andrey Korolyov and...@xdel.ru: On Mon, Feb 16, 2015 at 5:47 PM, Stefan Priebe - Profihost AG s.pri...@profihost.ag wrote: Hi, Am 16.02.2015 um 15:44 schrieb Paolo Bonzini: On 16/02/2015 15:43, Stefan Priebe - Profihost AG wrote: Hi, Am 16.02.2015 um 13:24 schrieb Paolo Bonzini: On 15/02/2015 19:46, Stefan Priebe wrote: while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. http://wiki.qemu.org/Contribute/ReportABug What is your command line? Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Hi Stefan, splitdebug will help you there. Also this is a standard way to ship debugging symbols in most distribuitions, so I wonder if you may use just a generic build skeleton for this task... I'm using enable-debug with dh_strip from Debian Stefan
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Am 16.02.2015 um 15:49 schrieb Paolo Bonzini pbonz...@redhat.com: On 16/02/2015 15:47, Stefan Priebe - Profihost AG wrote: Could it be that this is a results of compiling qemu with --enable-debug to get debugging symbols? Yes. *urg* my fault - sorry. Is there a way to get debugging symbols without using enable-debug / getting slower performance? Yes, just do nothing (--enable-debug-info is the default; --enable-debug enables debug info _and_ turns off optimization). If I do not enable-debug dh_strip does not extract any debugging symbols. Stefan Paolo
Re: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2
H Stefan, only for write ? or also read ? I'll try to reproduce on my test cluster. - Mail original - De: Stefan Priebe s.pri...@profihost.ag À: qemu-devel qemu-devel@nongnu.org Envoyé: Dimanche 15 Février 2015 19:46:12 Objet: [Qemu-devel] slow speed for virtio-scsi since qemu 2.2 Hi, while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. Is there a known regression? Greets, Stefan
[Qemu-devel] slow speed for virtio-scsi since qemu 2.2
Hi, while i get a constant random 4k i/o write speed of 20.000 iops with qemu 2.1.0 or 2.1.3. I get jumping speeds with qemu 2.2 (jumping between 500 iops and 15.000 iop/s). If i use virtio instead of virtio-scsi speed is the same between 2.2 and 2.1. Is there a known regression? Greets, Stefan
