Percona-Tookit工具包之pt-stalk

 

Preface

 

    We have a lot of methods to diagnose problems in our system such as strace,pstack,gstack,gdb,pt-pmp,etc.But sometimes there will be some fitful performance issues which are not so easy to trace.Thus,pt-stalk may help us in diagnosing these kind of problems.

 

Introduce

 

    pt-stalk is a tool to collect detail diagnostic data base on triggers you specified such as gdb,oprofile,strace,tcpdump.The trigger is not the conception of trigger in database.They're different at all.pt-stalk provides various options to collect comprehensive data you need.It's really useful and helpful in performance diagnosing.Let's see some details of it.

 

Procedure

 

Usage

 pt-stalk [OPTIONS]

Common Parameters

 --collect //Collect diagostic data based on spedified triggers.
 --collect-gdb //Collect gdb data.It prints stack traces from all threads.
 --collect-oprofile //Collect oprofile data.
 --collect-strace //Collect strace data.Do not specify it when "--collect-gdb" has been used.
 --collect-tcpdump //Collect tcpdump data.
 --cycles //Limite the times when triggering condition occurs(default "5").
 --dest //Specify the position to store diagnostic data(default "/var/lib/pt-stalk").
 --disk-bytes-free //Prevent the lack of least disk space.It does not collect data until it has the necessary disk space(default "100M",valid surffixes of unit is k,M,G and T).
 --disk-pct-free //It's similar with "--disk-bytes-free" but specify the percentage of disk space.
 --function //Specify the contents to watch for the triggers(default "status",other value is "processlist" or <yourfilename>).
 --iterations //Limit the times to collect.It will run forever if not give a specific value.
 --log //Specify the postion to record logs(default "/var/log/pt-stalk.log").It only generates when deamonized.
 --match //The pattern to specify when using "--function processlist".
 --mysql-only //Merely collect the MySQL relevant diagnostic data but disk space is the exception.
 --retention-time //Specify the purge days of diagnostic data(default "30").
 --run-time //Specify how many seconds to collect diagnostic data(default "30").It should not be longer than the value of "--sleep".
 --sleep //Specify how many seconds to sleep after last collection.It used to prevent too many operations of collection(default "300").
 --stalk //Watch and wait for trigger occur(default "yes").
 --no_stalk //The option can be specify if you want to collect diagnostic data immediately without waiting for trigger to occur.
 --threshold //Specify the maximum value for collecting(default "25").
 --variable //Specify the variables to compared against(default "Threads_running").

Examples

 

Generate benchmark with sysbench.

 [root@zlm2 :: ~/sysbench-1.0/src/lua]
 #sysbench oltp_read_write.lua --mysql-host=192.168.1.101 --mysql-port= --mysql-user=zlm --mysql-password=aaron8219 --mysql-db=sysbench --tables= --table-size= --mysql-storage-engine=innodb cleanup
 sysbench 1.0. (using bundled LuaJIT 2.1.-beta2)

 Dropping table 'sbtest1'...
 Dropping table 'sbtest2'...
 Dropping table 'sbtest3'...
 Dropping table 'sbtest4'...
 Dropping table 'sbtest5'...
 Dropping table 'sbtest6'...
 Dropping table 'sbtest7'...
 Dropping table 'sbtest8'...
 Dropping table 'sbtest9'...
 Dropping table 'sbtest10'...

 [root@zlm2 :: ~/sysbench-1.0/src/lua]
 #sysbench oltp_read_write.lua --mysql-host=192.168.1.101 --mysql-port= --mysql-user=zlm --mysql-password=aaron8219 --mysql-db=sysbench --tables= --table-size= --mysql-storage-engine=innodb prepare
 sysbench 1.0. (using bundled LuaJIT 2.1.-beta2)

 Creating table 'sbtest1'...
 Inserting  records into 'sbtest1'
 Creating a secondary index on 'sbtest1'...
 Creating table 'sbtest2'...
 Inserting  records into 'sbtest2'
 Creating a secondary index on 'sbtest2'...
 Creating table 'sbtest3'...
 Inserting  records into 'sbtest3'
 Creating a secondary index on 'sbtest3'...
 Creating table 'sbtest4'...
 Inserting  records into 'sbtest4'
 Creating a secondary index on 'sbtest4'...
 Creating table 'sbtest5'...
 Inserting  records into 'sbtest5'
 Creating a secondary index on 'sbtest5'...
 Creating table 'sbtest6'...
 Inserting  records into 'sbtest6'
 Creating a secondary index on 'sbtest6'...
 Creating table 'sbtest7'...
 Inserting  records into 'sbtest7'
 Creating a secondary index on 'sbtest7'...
 Creating table 'sbtest8'...
 Inserting  records into 'sbtest8'
 Creating a secondary index on 'sbtest8'...
 Creating table 'sbtest9'...
 Inserting  records into 'sbtest9'
 Creating a secondary index on 'sbtest9'...
 Creating table 'sbtest10'...
 Inserting  records into 'sbtest10'
 Creating a secondary index on 'sbtest10'...

 [root@zlm2 :: ~/sysbench-1.0/src/lua]
 #sysbench oltp_read_write.lua --mysql-host=192.168.1.101 --mysql-port= --mysql-user=zlm --mysql-password=aaron8219 --mysql-db=sysbench --threads= --time= --report-interval= --rand-type=uniform run
 sysbench 1.0. (using bundled LuaJIT 2.1.-beta2)

 Running the test with following options:
 Number of threads:
 Report intermediate results every  second(s)
 Initializing random number generator from current time

 Initializing worker threads...

 Threads started!

 [ 10s ] thds:  tps: 258.68 qps: 5176.49 (r/w/o: 3624.11/1034.82/517.56) lat (ms,%): 15.83 err/s: 0.00 reconn/s: 0.00
 [ 20s ] thds:  tps: 286.25 qps: 5726.15 (r/w/o: 4008.67/1144.89/572.60) lat (ms,%): 15.00 err/s: 0.00 reconn/s: 0.00
 [ 30s ] thds:  tps: 270.82 qps: 5416.13 (r/w/o: 3790.80/1083.69/541.64) lat (ms,%): 16.12 err/s: 0.00 reconn/s: 0.00
 [ 40s ] thds:  tps: 280.98 qps: 5619.75 (r/w/o: 3934.26/1123.53/561.97) lat (ms,%): 16.12 err/s: 0.00 reconn/s: 0.00
 [ 50s ] thds:  tps: 298.42 qps: 5968.38 (r/w/o: 4177.83/1193.70/596.85) lat (ms,%): 14.46 err/s: 0.00 reconn/s: 0.00
 [ 60s ] thds:  tps: 278.88 qps: 5578.20 (r/w/o: 3904.92/1115.52/557.76) lat (ms,%): 15.83 err/s: 0.00 reconn/s: 0.00
 [ 70s ] thds:  tps: 280.91 qps: 5617.66 (r/w/o: 3932.21/1123.63/561.82) lat (ms,%): 15.83 err/s: 0.00 reconn/s: 0.00
 [ 80s ] thds:  tps: 281.68 qps: 5632.83 (r/w/o: 3942.77/1126.71/563.35) lat (ms,%): 16.12 err/s: 0.00 reconn/s: 0.00
 [ 90s ] thds:  tps: 281.60 qps: 5631.55 (r/w/o: 3942.07/1126.39/563.10) lat (ms,%): 16.12 err/s: 0.00 reconn/s: 0.00
 [ 100s ] thds:  tps: 287.62 qps: 5753.86 (r/w/o: 4028.02/1150.49/575.35) lat (ms,%): 15.55 err/s: 0.00 reconn/s: 0.00
 [ 110s ] thds:  tps: 308.99 qps: 6180.45 (r/w/o: 4326.12/1236.35/617.97) lat (ms,%): 13.95 err/s: 0.00 reconn/s: 0.00
 ... //Omitted.

Collect diagnostic data using pt-stalk.

 [root@zlm2 :: /data/mysql/mysql3306]
 #pt-stalk --host localhost --port  --user root --password Passw0rd --collect-gdb --cycles  --variable Threads_connect --threshold
 mysql: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_46 Starting /usr/bin/pt-stalk --function=status --variable=Threads_connect --threshold= --match= --cycles= --interval= --iterations= --run-time= --sleep= --dest=/var/lib/pt-stalk --prefix= --notify-by-email= --log=/var/log/pt-stalk.log --pid=/var/run/pt-stalk.pid --plugin=
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_46 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_47 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_48 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_50 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_51 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_52 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_53 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_54 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_55 Detected value is empty; something failed?  Trigger exit status:
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_15_56 Detected value is empty; something failed?  Trigger exit status:
 ^C2018_07_09_08_15_57 Caught signal, exiting
 2018_07_09_08_15_57 All subprocesses have finished
 2018_07_09_08_15_57 Exiting because OKTORUN is false
 2018_07_09_08_15_57 /usr/bin/pt-stalk exit status 

 //The value of "--variable" should be "Threads_connected".
 //Modify the correct value and run it again.

 [root@zlm2 :: /data/mysql/mysql3306]
 #pt-stalk --host localhost --port  --user root --password Passw0rd --collect-gdb --cycles  --variable Threads_connected --threshold
 mysql: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_19_39 Starting /usr/bin/pt-stalk --function=status --variable=Threads_connected --threshold= --match= --cycles= --interval= --iterations= --run-time= --sleep= --dest=/var/lib/pt-stalk --prefix= --notify-by-email= --log=/var/log/pt-stalk.log --pid=/var/run/pt-stalk.pid --plugin=
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_19_39 Check results: status(Threads_connected)=, matched=yes, cycles_true=
 2018_07_09_08_19_39 Collect  triggered
 2018_07_09_08_19_39 Collect  PID
 2018_07_09_08_19_39 Collect  done
 2018_07_09_08_19_39 Sleeping  seconds after collect
 mysqladmin: [Warning] Using a password on the command line interface can be insecure.
 2018_07_09_08_24_39 Check results: status(Threads_connected)=, matched=yes, cycles_true=
 2018_07_09_08_24_39 Collect  triggered
 2018_07_09_08_24_39 Collect  PID
 2018_07_09_08_24_39 Collect  done
 2018_07_09_08_24_40 Sleeping  seconds after collect
 ^C2018_07_09_08_25_56 Caught signal, exiting //Terminate to collect diagnostic data by "Ctrl+C"
 2018_07_09_08_25_56 Waiting up to  seconds for subprocesses to finish...
 2018_07_09_08_25_56 Exiting because OKTORUN is false
 2018_07_09_08_25_56 /usr/bin/pt-stalk exit status 

Check the value of "show global status ... ".

 (root@localhost mysql3306.sock)[sysbench]>show global status like '%Threads%';
 +------------------------+-------+
 | Variable_name          | Value |
 +------------------------+-------+
 | Delayed_insert_threads |      |
 | Slow_launch_threads    |      |
 | Threads_cached         |      |
 | Threads_connected      |      | //Threads_connected has been up to 5.
 | Threads_created        |      |
 | Threads_running        |      |
 +------------------------+-------+
  rows in set (0.04 sec)

 (root@localhost mysql3306.sock)[sysbench]>show global status like '%Threads%';
 +------------------------+-------+
 | Variable_name          | Value |
 +------------------------+-------+
 | Delayed_insert_threads |      |
 | Slow_launch_threads    |      |
 | Threads_cached         |      |
 | Threads_connected      |      | //Second time,Threads_connected has been up to 6.
 | Threads_created        |      |
 | Threads_running        |      |
 +------------------------+-------+
  rows in set (0.01 sec)

Check the output files in default directory("/var/lib/pt-stalk").

 [root@zlm2 :: /var/lib/pt-stalk]
 #ls -lrt
 total
 -rw-r--r--  root root      Jul   : 2018_07_09_08_19_39-trigger
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-pmap
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-variables
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-innodbstatus1
 -rw-r--r--  root root      Jul   : 2018_07_09_08_19_39-mutex-status1
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-ps
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-lsof
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-opentables1
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-top
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-sysctl
 -rw-r--r--  root root      Jul   : 2018_07_09_08_19_39-disk-space
 -rw-r--r--  root root  Jul   : 2018_07_09_08_19_39-mysqladmin
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-vmstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-procstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-diskstats
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-procvmstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-netstat_s
 -rw-r--r--  root root   Jul   : 2018_07_09_08_19_39-slabinfo
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-interrupts
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-netstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-meminfo
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-df
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-processlist
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-innodbstatus2
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-transactions
 -rw-r--r--  root root        Jul   : 2018_07_09_08_19_39-hostname
 -rw-r--r--  root root      Jul   : 2018_07_09_08_19_39-mutex-status2
 -rw-r--r--  root root     Jul   : 2018_07_09_08_19_39-opentables2
 -rw-r--r--  root root      Jul   : 2018_07_09_08_19_39-vmstat-overall
 -rw-r--r--  root root    Jul   : 2018_07_09_08_19_39-output

 //There're a series of files(starts with "tigger" and ends with "output") each time we collect the diagnostic data.

 -rw-r--r--  root root      Jul   : 2018_07_09_08_24_39-trigger
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-pmap
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-variables
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-innodbstatus1
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-ps
 -rw-r--r--  root root      Jul   : 2018_07_09_08_24_39-mutex-status1
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-sysctl
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-lsof
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-opentables1
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-top
 -rw-r--r--  root root      Jul   : 2018_07_09_08_24_39-disk-space
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-vmstat
 -rw-r--r--  root root  Jul   : 2018_07_09_08_24_39-mysqladmin
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-procstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-netstat
 -rw-r--r--  root root   Jul   : 2018_07_09_08_24_39-slabinfo
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-netstat_s
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-interrupts
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-meminfo
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-diskstats
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-df
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-procvmstat
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-processlist
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-innodbstatus2
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-transactions
 -rw-r--r--  root root        Jul   : 2018_07_09_08_24_39-hostname
 -rw-r--r--  root root      Jul   : 2018_07_09_08_24_39-mutex-status2
 -rw-r--r--  root root     Jul   : 2018_07_09_08_24_39-opentables2
 -rw-r--r--  root root      Jul   : 2018_07_09_08_24_39-vmstat-overall
 -rw-r--r--  root root    Jul   : 2018_07_09_08_24_39-output

 [root@zlm2 :: /var/lib/pt-stalk]
 #cat 2018_07_09_08_24_39-trigger
 2018_07_09_08_24_39 Check results: status(Threads_connected)=, matched=yes, cycles_true=
 2018_07_09_08_24_39 pt-stalk ran with --function=status --variable=Threads_connected --threshold= --match= --cycles= --interval= --iterations= --run-time= --sleep= --dest=/var/lib/pt-stalk --prefix= --notify-by-email= --log=/var/log/pt-stalk.log --pid=/var/run/pt-stalk.pid --plugin=

 //The trigger file records the options we have used.

 [root@zlm2 :: /var/lib/pt-stalk]
 #cat 2018_07_09_08_24_39-vmstat-overall
 procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu-----
  r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st

  //The vmstat-overall records the vmstat output.
  //each file contains the relevant diagnostic data about what their name called.I'm not going to demonstrate all of them.

Take care of you remain disk space,pt-stalk won't run anymore if you're out of space.

 [root@zlm2 :: /data/mysql/mysql3306]
 #pt-stalk --host localhost --port  --user root --password Passw0rd --collect --cycles  --variable Threads_connected --threshold  --sleep  --demonize
 Cannot open /tmp/pt-stalk..FSboRq/po/daemonize: No space left on device at -e line , <$fh> chunk .
 No long attribute in option spec /tmp/pt-stalk..FSboRq/po/ask-pass

 [root@zlm2 :: /data/mysql/mysql3306]
 #df -h
 ]Filesystem               Size  Used Avail Use% Mounted on
 /dev/mapper/centos-root  .4G  .4G   20K % / //The root of linux has been out of space.
 devtmpfs                 488M       488M   % /dev
 tmpfs                    497M       497M   % /dev/shm
 tmpfs                    497M  6.6M  491M   % /run
 tmpfs                    497M       497M   % /sys/fs/cgroup
 /dev/sda1                497M  118M  379M  % /boot
 none                      87G   81G  .9G  % /vagrant

Summary

• pt-stalk is another tool in diagnosing system performance and similar with pt-pmp but not the same.
• pt-stalk will generate many statistic files which can really help you collecting information in almost every aspect.
• pt-stalk has four main triggers:gdb,oprofile,strace,tcpdump.It's flexible to collect data with diffrent dimensionality.