Google Git
Sign in
qemu / qemu / 44277bf914471962c9e88e09c859aae65ae109c4
commit44277bf914471962c9e88e09c859aae65ae109c4[log] [tgz]
authorStefan Hajnoczi <stefanha@redhat.com>Thu Aug 06 14:18:02 2020 +0100
committerStefan Hajnoczi <stefanha@redhat.com>Thu Aug 13 13:34:14 2020 +0100
tree0f121653a21378b00e3605f85e154ec486629f91
parent601829f88e0eff8f54fa08b7a69b0774a9c259c8 [diff]
aio-posix: keep aio_notify_me disabled during polling

Polling only monitors the ctx->notified field and does not need the
ctx->notifier EventNotifier to be signalled. Keep ctx->aio_notify_me
disabled while polling to avoid unnecessary EventNotifier syscalls.

This optimization improves virtio-blk 4KB random read performance by
18%. The following results are with an IOThread and the null-co block
driver:

Test         IOPS   Error
Before  244518.62 ± 1.20%
After   290706.11 ± 0.44%

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200806131802.569478-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
1 file changed
tree: 0f121653a21378b00e3605f85e154ec486629f91
  1. .github/
  2. .gitlab-ci.d/
  3. accel/
  4. audio/
  5. authz/
  6. backends/
  7. block/
  8. bsd-user/
  9. chardev/
  10. contrib/
  11. crypto/
  12. default-configs/
  13. disas/
  14. docs/
  15. dump/
  16. fpu/
  17. fsdev/
  18. gdb-xml/
  19. hw/
  20. include/
  21. io/
  22. libdecnumber/
  23. linux-headers/
  24. linux-user/
  25. migration/
  26. monitor/
  27. nbd/
  28. net/
  29. pc-bios/
  30. plugins/
  31. po/
  32. python/
  33. qapi/
  34. qga/
  35. qobject/
  36. qom/
  37. replay/
  38. roms/
  39. scripts/
  40. scsi/
  41. softmmu/
  42. storage-daemon/
  43. stubs/
  44. target/
  45. tcg/
  46. tests/
  47. tools/
  48. trace/
  49. ui/
  50. util/
  51. capstone
  52. dtc
  53. slirp
  54. .cirrus.yml
  55. .dir-locals.el
  56. .editorconfig
  57. .exrc
  58. .gdbinit
  59. .gitignore
  60. .gitlab-ci.yml
  61. .gitmodules
  62. .gitpublish
  63. .mailmap
  64. .patchew.yml
  65. .readthedocs.yml
  66. .shippable.yml
  67. .travis.yml
  68. block.c
  69. blockdev-nbd.c
  70. blockdev.c
  71. blockjob.c
  72. bootdevice.c
  73. Changelog
  74. CODING_STYLE.rst
  75. configure
  76. COPYING
  77. COPYING.LIB
  78. cpus-common.c
  79. device_tree.c
  80. disas.c
  81. dma-helpers.c
  82. exec-vary.c
  83. exec.c
  84. gdbstub.c
  85. gitdm.config
  86. hmp-commands-info.hx
  87. hmp-commands.hx
  88. iothread.c
  89. job-qmp.c
  90. job.c
  91. Kconfig
  92. Kconfig.host
  93. LICENSE
  94. MAINTAINERS
  95. Makefile
  96. Makefile.objs
  97. Makefile.target
  98. memory_ldst.inc.c
  99. module-common.c
  100. os-posix.c
  101. os-win32.c
  102. qdev-monitor.c
  103. qemu-bridge-helper.c
  104. qemu-edid.c
  105. qemu-img-cmds.hx
  106. qemu-img.c
  107. qemu-io-cmds.c
  108. qemu-io.c
  109. qemu-keymap.c
  110. qemu-nbd.c
  111. qemu-options-wrapper.h
  112. qemu-options.h
  113. qemu-options.hx
  114. qemu-seccomp.c
  115. qemu-storage-daemon.c
  116. qemu.nsi
  117. qemu.sasl
  118. README.rst
  119. replication.c
  120. replication.h
  121. rules.mak
  122. thunk.c
  123. tpm.c
  124. trace-events
  125. VERSION
  126. version.rc