Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-27 Thread Michael S. Tsirkin
On Thu, Feb 27, 2014 at 11:11:07AM +0800, Jason Wang wrote: > On 02/26/2014 05:23 PM, Michael S. Tsirkin wrote: > > On Wed, Feb 26, 2014 at 03:11:21PM +0800, Jason Wang wrote: > >> > On 02/26/2014 02:32 PM, Qin Chuanyu wrote: > >>> > >On 2014/2/26 13:53, Jason Wang wrote: > > >>On 02/25/2014 0

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-26 Thread Jason Wang
On 02/26/2014 05:23 PM, Michael S. Tsirkin wrote: > On Wed, Feb 26, 2014 at 03:11:21PM +0800, Jason Wang wrote: >> > On 02/26/2014 02:32 PM, Qin Chuanyu wrote: >>> > >On 2014/2/26 13:53, Jason Wang wrote: > >>On 02/25/2014 09:57 PM, Michael S. Tsirkin wrote: > > >>>On Tue, Feb 25, 2014 at

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-26 Thread Michael S. Tsirkin
On Wed, Feb 26, 2014 at 03:11:21PM +0800, Jason Wang wrote: > On 02/26/2014 02:32 PM, Qin Chuanyu wrote: > >On 2014/2/26 13:53, Jason Wang wrote: > >>On 02/25/2014 09:57 PM, Michael S. Tsirkin wrote: > >>>On Tue, Feb 25, 2014 at 02:53:58PM +0800, Jason Wang wrote: > We used to stop the handling

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-25 Thread Jason Wang
On 02/26/2014 02:32 PM, Qin Chuanyu wrote: On 2014/2/26 13:53, Jason Wang wrote: On 02/25/2014 09:57 PM, Michael S. Tsirkin wrote: On Tue, Feb 25, 2014 at 02:53:58PM +0800, Jason Wang wrote: We used to stop the handling of tx when the number of pending DMAs exceeds VHOST_MAX_PEND. This is used

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-25 Thread Qin Chuanyu
On 2014/2/26 13:53, Jason Wang wrote: On 02/25/2014 09:57 PM, Michael S. Tsirkin wrote: On Tue, Feb 25, 2014 at 02:53:58PM +0800, Jason Wang wrote: We used to stop the handling of tx when the number of pending DMAs exceeds VHOST_MAX_PEND. This is used to reduce the memory occupation of both hos

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-25 Thread Jason Wang
On 02/25/2014 09:57 PM, Michael S. Tsirkin wrote: On Tue, Feb 25, 2014 at 02:53:58PM +0800, Jason Wang wrote: We used to stop the handling of tx when the number of pending DMAs exceeds VHOST_MAX_PEND. This is used to reduce the memory occupation of both host and guest. But it was too aggressive

Re: [PATCH net] vhost: net: switch to use data copy if pending DMAs exceed the limit

2014-02-25 Thread Michael S. Tsirkin
On Tue, Feb 25, 2014 at 02:53:58PM +0800, Jason Wang wrote: > We used to stop the handling of tx when the number of pending DMAs > exceeds VHOST_MAX_PEND. This is used to reduce the memory occupation > of both host and guest. But it was too aggressive in some cases, since > any delay or blocking of