Catalog

0. bcc install

0.1 yum install

0.2 Source code installation

1. cachestat 

2. cachetop 

3. funccount

4. trace

4.1 trace

4.2 trace View its passed in parameters

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bcc All the tools provided are installed in /usr/share/bcc/tools In this directory . But here's a reminder ,bcc By default, the software package will not configure these tools to the system PATH In the path , So you have to configure it manually ：

$ export PATH=$PATH:/usr/share/bcc/tools

0. bcc install

0.1 yum install

yum install bcc-tools

0.2 Source code installation

Install build dependencies：
sudo yum groupinstall -y "Development tools"
sudo yum install -y elfutils-libelf-devel cmake3 git bison flex ncurses-devel
sudo yum install -y luajit luajit-devel  # for Lua support

Install and compile LLVM：
curl  -LO  http://releases.llvm.org/7.0.1/llvm-7.0.1.src.tar.xz
curl  -LO  http://releases.llvm.org/7.0.1/cfe-7.0.1.src.tar.xz
tar -xf cfe-7.0.1.src.tar.xz
tar -xf llvm-7.0.1.src.tar.xz

mkdir clang-build
mkdir llvm-build

cd llvm-build
cmake3 -G "Unix Makefiles" -DLLVM_TARGETS_TO_BUILD="BPF;X86" \
  -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr ../llvm-7.0.1.src
make
sudo make install

cd ../clang-build
cmake3 -G "Unix Makefiles" -DLLVM_TARGETS_TO_BUILD="BPF;X86" \
  -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr ../cfe-7.0.1.src
make
sudo make install
cd ..

Install and compile BCC：
git clone GitHub - iovisor/bcc: BCC - Tools for BPF-based Linux IO analysis, networking, monitoring, and more
mkdir bcc/build; cd bcc/build
cmake .. -DCMAKE_INSTALL_PREFIX=/usr
make
sudo make install

PS：
1. Use make Out of commission make -j8
2. ln -s python2 python # establish python Soft connection
3. make install route ：/usr/share/bcc/tools

 

1. cachestat 

./cachestat 1 3

   TOTAL   MISSES     HITS  DIRTIES   BUFFERS_MB  CACHED_MB

       0        0        0        0            3        303

       1        0        1        0            3        303

       0        0        0        0            3        303

You can see ,cachestat The output of is actually a table . Each row represents a set of data , And each column represents different cache statistics . These indicators represent... From left to right

TOTAL , Indicates total I/O frequency ;

MISSES , Indicates the number of cache misses ;

HITS , Indicates the number of cache hits ;

DIRTIES, Indicates the number of dirty pages added to the cache ;

BUFFERS_MB Express Buffers Size , With MB In units of ;

CACHED_MB Express Cache Size , With MB In units of .

2. cachetop 

./cachetop 

13:52:30 Buffers MB: 3 / Cached MB: 391 / Sort: HITS / Order: ascending
PID      UID      CMD              HITS     MISSES   DIRTIES  READ_HIT%  WRITE_HIT%
    1506 root     cachetop                1        0        0     100.0%       0.0%
    1534 nginx    nginx                   1        3        0      25.0%      50.0%
    1544 root     curl                   20        0        0     100.0%       0.0%
    1543 root     bash                  198        4        0      98.0%       2.0%
    1543 root     curl                 1993       80        0      96.1%       3.9%

Its output is similar to top similar , The default is based on the number of hits in the cache （HITS） Sort , Shows the cache hits of each process . Specific to each indicator , there HITS、MISSES and DIRTIES , Follow cachestat The same meaning in , Each represents the number of cache hits in the interval 、 Number of misses and dirty pages added to the cache .

and READ_HIT and WRITE_HIT , Indicates the cache hit rate of read and write respectively .

3. funccount

./funccount -i 1 c:malloc

Tracing 1 functions for "b'c:malloc'"... Hit Ctrl-C to end.

FUNC                                    COUNT
b'malloc'                                   2

FUNC                                    COUNT
b'malloc'                                   1

FUNC                                    COUNT
b'malloc'                                   1

FUNC                                    COUNT
b'malloc'                                   1

FUNC                                    COUNT
b'malloc'                                   1

funccount  Some parameters are supported , such as -p Specify a process ID, -i Specify the time interval for the output . At present, it can only support up to 1000 A tracking object (probe), about fmt.* Come on , There are not many functions OK, But if you track all libgo There is a problem with the function in

# funccount 'go:*'
maximum of 1000 probes allowed, attempted 21178

Uh huh , No more work . It's like bcc/BPF Like some other problems in , If this limitation hinders the application too much, we should consider finding a way to solve it .

4. trace

4.1 trace

./trace do_sys_open
PID     TID     COMM            FUNC            
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
1       1       systemd         do_sys_open     
1       1       systemd         do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
1       1       systemd         do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open     
832     832     irqbalance      do_sys_open  

4.2 trace View its passed in parameters

./trace '/root/bcc_test/test_malloc:add "%d %d" arg1, arg2' PID TID COMM FUNC - 1691 1691 test_malloc add 2 3 1692 1692 test_malloc add 2 3 1693 1693 test_malloc add 2 3 1694 1694 test_malloc add 2 3 1695 1695 test_malloc add 2 3 1696 1696 test_malloc add 2 3