mirror of https://gitee.com/openkylin/qemu.git
d37d0e365a
When there are many poll handlers it's likely that some of them are idle most of the time. Remove handlers that haven't had activity recently so that the polling loop scales better for guests with a large number of devices. This feature only takes effect for the Linux io_uring fd monitoring implementation because it is capable of combining fd monitoring with userspace polling. The other implementations can't do that and risk starving fds in favor of poll handlers, so don't try this optimization when they are in use. IOPS improves from 10k to 105k when the guest has 100 virtio-blk-pci,num-queues=32 devices and 1 virtio-blk-pci,num-queues=1 device for rw=randread,iodepth=1,bs=4k,ioengine=libaio on NVMe. [Clarified aio_poll_handlers locking discipline explanation in comment after discussion with Paolo Bonzini <pbonzini@redhat.com>. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://lore.kernel.org/r/20200305170806.1313245-8-stefanha@redhat.com Message-Id: <20200305170806.1313245-8-stefanha@redhat.com> |
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| block | ||
| chardev | ||
| crypto | ||
| disas | ||
| exec | ||
| fpu | ||
| hw | ||
| io | ||
| libdecnumber | ||
| migration | ||
| monitor | ||
| net | ||
| qapi | ||
| qemu | ||
| qom | ||
| scsi | ||
| standard-headers | ||
| sysemu | ||
| tcg | ||
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| elf.h | ||
| glib-compat.h | ||
| qemu-common.h | ||
| qemu-io.h | ||
| trace-tcg.h | ||