-// Top like progream which collects information from MySQL's
+// pstop - Top like progream which collects information from MySQL's
// performance_schema database.
package main
import (
"database/sql"
+ "errors"
"flag"
"fmt"
"log"
"os"
"os/signal"
+ "regexp"
"runtime/pprof"
"syscall"
"time"
"github.com/sjmudd/pstop/lib"
"github.com/sjmudd/pstop/state"
"github.com/sjmudd/pstop/version"
+ "github.com/sjmudd/pstop/wait_info"
)
const (
db = "performance_schema"
)
-var flag_version = flag.Bool("version", false, "Show the version of "+lib.MyName())
-var flag_debug = flag.Bool("debug", false, "Enabling debug logging")
-var flag_help = flag.Bool("help", false, "Provide some help for "+lib.MyName())
-var cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
+var (
+ flag_debug = flag.Bool("debug", false, "Enabling debug logging")
+ flag_defaults_file = flag.String("defaults-file", "", "Provide a defaults-file to use to connect to MySQL")
+ flag_help = flag.Bool("help", false, "Provide some help for "+lib.MyName())
+ flag_host = flag.String("host", "", "Provide the hostname of the MySQL to connect to")
+ flag_port = flag.Int("port", 0 , "Provide the port number of the MySQL to connect to (default: 3306)") /* deliberately 0 here, defaults to 3306 elsewhere */
+ flag_socket = flag.String("socket", "", "Provide the path to the local MySQL server to connect to")
+ flag_password = flag.String("password", "", "Provide the password when connecting to the MySQL server")
+ flag_user = flag.String("user", "", "Provide the username to connect with to MySQL (default: $USER)")
+ flag_version = flag.Bool("version", false, "Show the version of "+lib.MyName())
+ cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
-func get_db_handle() *sql.DB {
+ re_valid_version = regexp.MustCompile(`^(5\.[67]\.|10\.[01])`)
+)
+
+// Connect to the database with the given defaults-file, or ~/.my.cnf if not provided.
+func connect_by_defaults_file( defaults_file string ) *sql.DB {
+ var err error
+ var dbh *sql.DB
+ lib.Logger.Println("connect_by_defaults_file() connecting to database")
+
+ dbh, err = mysql_defaults_file.OpenUsingDefaultsFile(sql_driver, defaults_file, "performance_schema")
+ if err != nil {
+ log.Fatal(err)
+ }
+ if err = dbh.Ping(); err != nil {
+ log.Fatal(err)
+ }
+
+ // deliberately limit the pool size to 5 to avoid "problems" if any queries hang.
+ dbh.SetMaxOpenConns(5) // hard-coded value!
+
+ return dbh
+}
+
+// connect to MySQL using various component parts needed to make the dsn
+func connect_by_components( components map[string]string ) *sql.DB {
var err error
var dbh *sql.DB
+ lib.Logger.Println("connect_by_components() connecting to database")
- dbh, err = mysql_defaults_file.OpenUsingDefaultsFile(sql_driver, "", "performance_schema")
+ new_dsn := mysql_defaults_file.BuildDSN(components, "performance_schema")
+ dbh, err = sql.Open(sql_driver, new_dsn)
if err != nil {
log.Fatal(err)
}
fmt.Println("Usage: " + lib.MyName() + " <options>")
fmt.Println("")
fmt.Println("Options:")
- fmt.Println("-help show this help message")
- fmt.Println("-version show the version")
+ fmt.Println("--defaults-file=/path/to/defaults.file Connect to MySQL using given defaults-file" )
+ fmt.Println("--help Show this help message")
+ fmt.Println("--version Show the version")
+ fmt.Println("--host=<hostname> MySQL host to connect to")
+ fmt.Println("--port=<port> MySQL port to connect to")
+ fmt.Println("--socket=<path> MySQL path of the socket to connect to")
+ fmt.Println("--user=<user> User to connect with")
+ fmt.Println("--password=<password> Password to use when connecting")
+}
+
+// pstop requires MySQL 5.6+ or MariaDB 10.0+. Check the version
+// rather than giving an error message if the requires P_S tables can't
+// be found.
+func validate_mysql_version(dbh *sql.DB) error {
+ var tables = [...]string{
+ "performance_schema.events_waits_summary_global_by_event_name",
+ "performance_schema.file_summary_by_instance",
+ "performance_schema.table_io_waits_summary_by_table",
+ "performance_schema.table_lock_waits_summary_by_table",
+ }
+
+ lib.Logger.Println("validate_mysql_version()")
+
+ lib.Logger.Println("- Getting MySQL version")
+ err, mysql_version := lib.SelectGlobalVariableByVariableName(dbh, "VERSION")
+ if err != nil {
+ return err
+ }
+ lib.Logger.Println("- mysql_version: '" + mysql_version + "'")
+
+ if !re_valid_version.MatchString(mysql_version) {
+ err := errors.New(lib.MyName() + " does not work with MySQL version " + mysql_version)
+ return err
+ }
+ lib.Logger.Println("OK: MySQL version is valid, continuing")
+
+ lib.Logger.Println("Checking access to required tables:")
+ for i := range tables {
+ if err := lib.CheckTableAccess(dbh, tables[i]); err == nil {
+ lib.Logger.Println("OK: " + tables[i] + " found")
+ } else {
+ return err
+ }
+ }
+ lib.Logger.Println("OK: all table checks passed")
+
+ return nil
}
func main() {
+ var defaults_file string = ""
flag.Parse()
// clean me up
}
lib.Logger.Println("Starting " + lib.MyName())
+
+ var dbh *sql.DB
+
+ if *flag_host != "" || *flag_socket != "" {
+ lib.Logger.Println("--host= or --socket= defined")
+ var components = make(map[string]string)
+ if *flag_host != "" && *flag_socket != "" {
+ fmt.Println(lib.MyName() + ": Do not specify --host and --socket together" )
+ os.Exit(1)
+ }
+ if *flag_host != "" {
+ components["host"] = *flag_host
+ }
+ if *flag_port != 0 {
+ if *flag_socket == "" {
+ components["port"] = fmt.Sprintf("%d", *flag_port)
+ } else {
+ fmt.Println(lib.MyName() + ": Do not specify --socket and --port together" )
+ os.Exit(1)
+ }
+ }
+ if *flag_socket != "" {
+ components["socket"] = *flag_socket
+ }
+ if *flag_user != "" {
+ components["user"] = *flag_user
+ }
+ if *flag_password != "" {
+ components["password"] = *flag_password
+ }
+ dbh = connect_by_components( components )
+ } else {
+ if flag_defaults_file != nil && *flag_defaults_file != "" {
+ lib.Logger.Println("--defaults-file defined")
+ defaults_file = *flag_defaults_file
+ } else {
+ lib.Logger.Println("connecting by implicit defaults file")
+ }
+ dbh = connect_by_defaults_file( defaults_file )
+ }
+
+ if err := validate_mysql_version(dbh); err != nil {
+ log.Fatal(err)
+ }
+
var state state.State
+ var wi wait_info.WaitInfo
+ wi.SetWaitInterval(time.Second)
- interval := time.Second
sigChan := make(chan os.Signal, 1)
done := make(chan struct{})
defer close(done)
signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
- ticker := time.NewTicker(interval) // generate a periodic signal
-
- state.Setup(get_db_handle())
-
- finished := false
- for !finished {
+ state.Setup(dbh)
+ for !state.Finished() {
select {
case <-done:
fmt.Println("exiting")
- finished = true
+ state.SetFinished()
case sig := <-sigChan:
fmt.Println("Caught a signal", sig)
done <- struct{}{}
- case <-ticker.C:
+ case <-wi.WaitNextPeriod():
state.Collect()
+ wi.CollectedNow()
state.Display()
case event := <-termboxChan:
// switch on event type
case termbox.EventKey: // actions depend on key
switch event.Key {
case termbox.KeyCtrlZ, termbox.KeyCtrlC, termbox.KeyEsc:
- finished = true
- case termbox.KeyTab: // tab - change display modes
+ state.SetFinished()
+ case termbox.KeyArrowLeft: // left arrow change to previous display mode
+ state.DisplayPrevious()
+ state.Display()
+ case termbox.KeyTab, termbox.KeyArrowRight: // tab or right arrow - change to next display mode
state.DisplayNext()
state.Display()
}
switch event.Ch {
case '-': // decrease the interval if > 1
- if interval > time.Second {
- ticker.Stop()
- interval -= time.Second
- ticker = time.NewTicker(interval)
+ if wi.WaitInterval() > time.Second {
+ wi.SetWaitInterval(wi.WaitInterval() - time.Second)
}
case '+': // increase interval by creating a new ticker
- ticker.Stop()
- interval += time.Second
- ticker = time.NewTicker(interval)
- case 'h': // help
+ wi.SetWaitInterval(wi.WaitInterval() + time.Second)
+ case 'h', '?': // help
state.SetHelp(!state.Help())
case 'q': // quit
- finished = true
+ state.SetFinished()
case 't': // toggle between absolute/relative statistics
state.SetWantRelativeStats(!state.WantRelativeStats())
state.Display()
}
}
state.Cleanup()
- ticker.Stop()
lib.Logger.Println("Terminating " + lib.MyName())
}