This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-devel] [PATCH 6/8] blkio-cgroup-v11: The document of blkio-cgroup

The document of blkio-cgroup.

Signed-off-by: Hirokazu Takahashi <taka@xxxxxxxxxxxxx>
Signed-off-by: Ryo Tsuruta <ryov@xxxxxxxxxxxxx>

 Documentation/cgroups/00-INDEX  |    2 +
 Documentation/cgroups/blkio.txt |   49 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

Index: linux-2.6.31-rc7/Documentation/cgroups/00-INDEX
--- linux-2.6.31-rc7.orig/Documentation/cgroups/00-INDEX
+++ linux-2.6.31-rc7/Documentation/cgroups/00-INDEX
@@ -16,3 +16,5 @@ memory.txt
        - Memory Resource Controller; design, accounting, interface, testing.
        - Resource Counter API.
+       - Block I/O Tracking; description, interface and examples.
Index: linux-2.6.31-rc7/Documentation/cgroups/blkio.txt
--- /dev/null
+++ linux-2.6.31-rc7/Documentation/cgroups/blkio.txt
@@ -0,0 +1,49 @@
+Block I/O Cgroup
+1. Overview
+Using this feature the owners of any type of I/O can be determined.
+This allows dm-ioband to control block I/O bandwidth even when it is
+accepting delayed write requests. dm-ioband can find the cgroup of
+each request. It is also for possible that others working on I/O
+bandwidth throttling to use this functionality to control asynchronous
+I/O with a little enhancement.
+2. Setting up blkio-cgroup
+The following kernel config options are required.
+Selecting the options for the cgroup memory subsystem is also recommended
+as it makes it possible to give some I/O bandwidth and memory to a selected
+cgroup to control delayed write requests. The amount of dirty pages is
+limited within the cgroup even if the allocated bandwidth is narrow.
+3. User interface
+3.1 Mounting the cgroup filesystem
+First, mount the cgroup filesystem in order to enable observation and
+modification of the blkio-cgroup settings.
+# mount -t cgroup -o blkio none /cgroup
+3.2 The blkio.id file
+After mounting the cgroup filesystem the blkio.id file will be visible
+in the cgroup directory. This file contains a unique ID number for
+each cgroup. When an I/O operation starts, blkio-cgroup sets the
+page's ID number on the page cgroup. The cgroup of I/O can be
+determined by retrieving the ID number from the page cgroup, because
+the page cgroup is associated with the page which is involved in the
+4. Contact
+Linux Block I/O Bandwidth Control Project

Xen-devel mailing list