Re: [libvirt] [RFC PATCH 0/8 v3] Summary on block IO throttle

On Thu, Nov 10, 2011 at 4:32 AM, Lei Li&lt;lilei(a)linux.vnet.ibm.com&gt; wrote: > Changes since V2 > - Implement the Python binding support for setting blkio throttling. > - Implement --current --live --config options support to unify the libvirt API. > - Add changes in docs and tests. > - Some changes suggested by Adam Litke, Eric Blake, Daniel P. Berrange. > - Change the XML schema. > - API name to virDomain{Set, Get}BlockIoTune. > - Parameters changed to make them more self-explanatory. > - virsh command name to blkdeviotune. > - And other fixups. > > Changes since V1 > - Implement the support to get the block io throttling for > a device as read only connection - QMP/HMP. > - Split virDomainBlockIoThrottle into two separate functions > virDomainSetBlockIoThrottle - Set block I/O limits for a device > - Requires a connection in 'write' mode. > - Limits (info) structure passed as an input parameter > virDomainGetBlockIoThrottle - Get the current block I/O limits for a device > - Works on a read-only connection. > - Current limits are written to the output parameter (reply). > - And Other fixups suggested by Adam Litke, Daniel P. Berrange. > - For dynamically allocate the blkiothrottle struct, I will fix > it when implement --current --live --config options support. > > Today libvirt supports the cgroups blkio-controller, which handles > proportional shares and throughput/iops limits on host block devices. > blkio-controller does not support network file systems (NFS) or other > QEMU remote block drivers (curl, Ceph/rbd, sheepdog) since they are > not host block devices. QEMU I/O throttling works with all types of > drive and can be applied independently to each drive attached to > a guest and supports throughput/iops limits. > > To help add QEMU I/O throttling support to libvirt, we plan to complete > it with add new API virDomain{Set, Get}BlockIoThrottle(), new command 'blkdeviotune' > and Python bindings. > > Notes: Now all the planed features were implemented (#1#2 were implemented by > Zhi Yong Wu), the previous comments were all fixed up too. And the qemu part patches > have been accepted upstream just now and are expected to be part of the QEMU 1.1 > release, git tree from Zhi Yong: > > http://repo.or.cz/w/qemu/kevin.git/shortlog/refs/heads/block > > > 1) Enable the blkio throttling in xml when guest is starting up. > > Add blkio throttling in xml as follows: > > <disk type='file' device='disk'> > ... > <iotune> > <total_bytes_sec>nnn</total_bytes_sec> > ... > </iotune> > ... > </disk> > > 2) Enable blkio throttling setting at guest running time. > > virsh blkdeviotune<domain> <device> [--total_bytes_sec<number>] [--read_bytes_sec<number>] \ > [--write_bytes_sec<number>] [--total_iops_sec<number>] [--read_iops_sec<number>] > [--write_iops_sec<number>] > > 3) The support to get the current block i/o throttling for a device - HMP/QMP. > > virsh blkiothrottle<domain> <device> > total_bytes_sec: > read_bytes_sec: > write_bytes_sec: > total_iops_sec: > read_iops_sec: > write_iops_sec: > > 4) Python binding support for setting blkio throttling. > 5) --current --live --config options support to unify the libvirt API. > > virsh blkdeviotune<domain> <device> [--total_bytes_sec<number>] [--read_bytes_sec<number>] > [--write_bytes_sec<number>] [--total_iops_sec<number>] [--read_iops_sec<number>] > [--write_iops_sec<number>] [--config] [--live] [--current] Thanks Li Lei for the remaining works. Below is only one reminder. QEMU command line options have some limitations as below: (1) global bps limit. -drive bps=xxx in bytes/s (2) only read bps limit -drive bps_rd=xxx in bytes/s (3) only write bps limit -drive bps_wr=xxx in bytes/s (4) global iops limit -drive iops=xxx in ios/s (5) only read iops limit -drive iops_rd=xxx in ios/s (6) only write iops limit -drive iops_wr=xxx in ios/s (7) the combination of some limits. -drive bps=xxx,iops=xxx Known Limitations: (1) #1 can not be used with #2, #3 together (2) #4 can not be used with #5, #6 together

> > > daemon/remote.c | 87 +++++++ > docs/formatdomain.html.in | 30 ++ > docs/schemas/domaincommon.rng | 24 + > include/libvirt/libvirt.h.in | 25 ++ > python/generator.py | 2 > python/libvirt-override-api.xml | 16 + > python/libvirt-override.c | 85 +++++++ > src/conf/domain_conf.c | 101 ++++++++ > src/conf/domain_conf.h | 12 > src/driver.h | 18 + > src/libvirt.c | 115 +++++++++ > src/libvirt_public.syms | 2 > src/qemu/qemu_command.c | 33 ++ > src/qemu/qemu_driver.c | 217 ++++++++++++++++++ > src/qemu/qemu_monitor.c | 36 ++ > src/qemu/qemu_monitor.h | 10 > src/qemu/qemu_monitor_json.c | 191 +++++++++++++++ > src/qemu/qemu_monitor_json.h | 10 > src/qemu/qemu_monitor_text.c | 152 ++++++++++++ > src/qemu/qemu_monitor_text.h | 10 > src/remote/remote_driver.c | 81 ++++++ > src/remote/remote_protocol.x | 39 +++ > src/remote_protocol-structs | 34 ++ > src/util/xml.h | 3 > tests/qemuxml2argvdata/qemuxml2argv-blkdeviotune.args | 4 > tests/qemuxml2argvdata/qemuxml2argv-blkdeviotune.xml | 36 ++ > tests/qemuxml2argvtest.c | 2 > tests/qemuxml2xmltest.c | 2 > tools/virsh.c | 146 ++++++++++++ > tools/virsh.pod | 23 + > 30 files changed, 1540 insertions(+), 6 deletions(-) > > -- > Lei > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list >