import (
"database/sql"
+ "errors"
"flag"
"fmt"
"log"
"os"
"os/signal"
+ "regexp"
+ "runtime/pprof"
"syscall"
"time"
db = "performance_schema"
)
+var (
+ flag_version = flag.Bool("version", false, "Show the version of "+lib.MyName())
+ flag_debug = flag.Bool("debug", false, "Enabling debug logging")
+ flag_help = flag.Bool("help", false, "Provide some help for "+lib.MyName())
+ cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
+
+ re_valid_version = regexp.MustCompile(`^(5\.[67]\.|10\.[01])`)
+)
+
func get_db_handle() *sql.DB {
var err error
var dbh *sql.DB
+ lib.Logger.Println("get_db_handle() connecting to database")
dbh, err = mysql_defaults_file.OpenUsingDefaultsFile(sql_driver, "", "performance_schema")
if err != nil {
fmt.Println("-version show the version")
}
+// 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.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 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())
flag.Parse()
// clean me up
+ if *cpuprofile != "" {
+ f, err := os.Create(*cpuprofile)
+ if err != nil {
+ log.Fatal(err)
+ }
+ pprof.StartCPUProfile(f)
+ defer pprof.StopCPUProfile()
+ }
+
if *flag_debug {
lib.Logger.EnableLogging(true)
}
}
lib.Logger.Println("Starting " + lib.MyName())
- var state state.State
+ dbh := get_db_handle()
+ if err := validate_mysql_version(dbh); err != nil {
+ log.Fatal(err)
+ }
+
+ var state state.State
interval := time.Second
sigChan := make(chan os.Signal, 1)
done := make(chan struct{})
ticker := time.NewTicker(interval) // generate a periodic signal
- state.Setup(get_db_handle())
+ state.Setup(dbh)
finished := false
for !finished {