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      1 The I/O bandwidth controller testplan includes a complete set of testcases to
      2 verify the effectiveness of the block device I/O throttling capabilities for
      3 cgroups.
      4 
      5 I/O bandwidth limitations are imposed by the testcase script and verified doing
      6 I/O activity on a limited block device. Tests are supposed to be passed if the
      7 I/O rates of all the different workloads always respect the I/O limitations.
      8 
      9 TESTCASE DESCRIPTION:
     10 ====================
     11 First of all we evaluate the physical I/O bandwidth (physical-io-bw) of the
     12 block device where the current working directory resides.
     13 
     14 Based on the physical I/O bandwidth three cgroups are created: cgroup-1,
     15 cgroup-2, cgroup-3. Cgroups use respectively the following I/O bandwidth
     16 limitations:
     17 - cgroup-1: physical-io-bw / 2
     18 - cgroup-2: physical-io-bw / 4
     19 - cgroup-3: physical-io-bw / 8
     20 
     21 Each test is considered passed only if the I/O limitations above are respected.
     22 
     23 Currently the following different scenarios are tested:
     24 - 1 single stream per cgroup using leaky-bucket I/O throttling
     25 - 1 single stream per cgroup using token-bucket I/O throttling
     26 - 2 parallel streams per cgroup using leaky-bucket I/O throttling
     27 - 2 parallel streams per cgroup using token-bucket I/O throttling
     28 - 4 parallel streams per cgroup using leaky-bucket I/O throttling
     29 - 4 parallel streams per cgroup using token-bucket I/O throttling
     30 
     31 For any other information please refer to
     32 Documentation/controllers/io-throttle.txt in kernel documentation.
     33 
     34 Questions?
     35 ----------
     36 Send email to: righi.andrea (a] gmail.com
     37