controllers/cpuset_memory_spread: #831
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When the cpuset_mem_hog program is run and the number of FilePages in the process is counted, the Page Cache of other processes interferes with the process, causing the use case to fail Other Page Cache comes from two aspects: 1. After releasing Page Cache and slab cache: echo 3> /proc/sys/vm/drop_caches, some processes or kernel threads will reload files into Page Cache 2. During the running of the cpuset_mem_hog program, there will be some processes using Page Cache amendment: 1, The first type of Page Cache: solve it by adding a delay after the echo 3> /proc/sys/vm/drop_caches command is executed: sleep 3 # 3 is an empirical value, and it may have a different value without the environment 2, The second type of Page Cache: by modifying the strategy, create a new sys: /dev/cpuset/cpuset/sys under the cpuset in the cgroup, and then add all user processes except cpuset_mem_hog to the cgroup, and set the strategy for the CPU and memory nodes Same as /dev/cpuset/cpuset/1
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Hi, thanks for the PR. There are some issues which I will comment on the code. |
| @@ -187,15 +187,23 @@ cleanup() | |||
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| find "$CPUSET" -type d | sort | sed -n '2,$p' | tac | while read subdir | |||
| do | |||
| if [ "$subdir" != "/dev/cpuset/sys" ]; then | |||
| while read pid | |||
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While should be indented.
| @@ -187,15 +187,23 @@ cleanup() | |||
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| find "$CPUSET" -type d | sort | sed -n '2,$p' | tac | while read subdir | |||
| do | |||
| if [ "$subdir" != "/dev/cpuset/sys" ]; then | |||
| fi | ||
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| if [ "$subdir" == "/dev/cpuset/sys" ]; then | ||
| cgdelete -r cpuset:sys |
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What is cgdelete?
It is not a shell function or program I have installed.
| @@ -194,6 +194,7 @@ result_check() | |||
| general_memory_spread_test() | |||
| { | |||
| local cpusetpath="$CPUSET/1" | |||
| local cpusetpathsys="$CPUSET/sys" | |||
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there appears to be an extra indent. Maybe you are mixing tabs and spaces?
| return 1 | ||
| fi | ||
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| array=`ps -elf |grep -v "\["|awk '{print $4}'|xargs echo` |
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What is this supposed to do and is it the simplest way to do it?
For example, could you do this by reading cgroup.procs or tasks in the root group or just using ps?
Also after we move all these processes, do they get moved back to where they came from?
Do we split the memory nodes between between group 1 and sys? I guess that one or more nodes need to be excluded from the test and assigned to sys. Assuming there are enough nodes available on the machine.
| @@ -224,6 +244,7 @@ general_memory_spread_test() | |||
| # we'd better drop the caches before we test page cache. | |||
| sync | |||
| /bin/echo 3 > /proc/sys/vm/drop_caches 2> $CPUSET_TMP/stderr | |||
| sleep 3 | |||
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Can the same thing be achieved by writing to /proc/sys/vm/stat_refresh?
Note that stat_refresh is not available on older kernels, in which case you can fall back to sleeping.
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@guohui0712 @richiejp I encountered the same problem， when I adjusted the lowerlimit from 2000 to 5000, the problem disappeared. |
When the cpuset_mem_hog program is run and
the number of FilePages in the process is counted,
the Page Cache of other processes interferes with the process,
causing the use case to fail
Other Page Cache comes from two aspects:
echo 3> /proc/sys/vm/drop_caches,
some processes or kernel threads will reload files into Page Cache
there will be some processes using Page Cache
amendment:
1, The first type of Page Cache: solve it by adding a delay after
the echo 3> /proc/sys/vm/drop_caches command is executed:
sleep 3 # 3 is an empirical value, and it may have a
different value without the environment
2, The second type of Page Cache: by modifying the strategy,
create a new sys: /dev/cpuset/cpuset/sys under the cpuset in the cgroup,
and then add all user processes except cpuset_mem_hog to the cgroup,
and set the strategy for the CPU and memory nodes
Same as /dev/cpuset/cpuset/1