--- /dev/null
+// This file contains the library routines for managing the
+// table_io_waits_by_table table.
+package events_waits_summary_global_by_event_name
+
+import (
+ "database/sql"
+ "fmt"
+ "log"
+ "sort"
+ "strings"
+
+ "github.com/sjmudd/pstop/lib"
+)
+
+// a row from performance_schema.events_waits_summary_global_by_event_name
+// Note: upper case names to match the performance_schema column names.
+// This type is _not_ meant to be exported.
+type events_waits_summary_global_by_event_name_row struct {
+ EVENT_NAME string
+ SUM_TIMER_WAIT uint64
+ COUNT_STAR uint64
+}
+type events_waits_summary_global_by_event_name_rows []events_waits_summary_global_by_event_name_row
+
+// trim off the leading 'wait/synch/mutex/innodb/'
+func (r *events_waits_summary_global_by_event_name_row) name() string {
+ var n string
+ if r.EVENT_NAME == "Totals" {
+ n += r.EVENT_NAME
+ } else if len(r.EVENT_NAME) >= 24 {
+ n += r.EVENT_NAME[24:]
+ }
+ return n
+}
+
+func (r *events_waits_summary_global_by_event_name_row) pretty_name() string {
+ s := r.name()
+ if len(s) > 30 {
+ s = s[:29]
+ }
+ return s
+}
+
+func (r *events_waits_summary_global_by_event_name_row) headings() string {
+ return fmt.Sprintf("%-30s %10s %6s", "Mutex Name", "Latency", "%")
+}
+
+// generate a printable result
+func (r *events_waits_summary_global_by_event_name_row) row_content(totals events_waits_summary_global_by_event_name_row) string {
+ name := r.pretty_name()
+ if r.COUNT_STAR == 0 && name != "Totals" {
+ name = ""
+ }
+
+ return fmt.Sprintf("%-30s %10s %6s",
+ name,
+ lib.FormatTime(r.SUM_TIMER_WAIT),
+ lib.FormatPct(lib.MyDivide(r.SUM_TIMER_WAIT, totals.SUM_TIMER_WAIT)))
+}
+
+func (this *events_waits_summary_global_by_event_name_row) add(other events_waits_summary_global_by_event_name_row) {
+ this.SUM_TIMER_WAIT += other.SUM_TIMER_WAIT
+ this.COUNT_STAR += other.COUNT_STAR
+}
+
+// subtract the countable values in one row from another
+func (this *events_waits_summary_global_by_event_name_row) subtract(other events_waits_summary_global_by_event_name_row) {
+ // check for issues here (we have a bug) and log it
+ // - this situation should not happen so there's a logic bug somewhere else
+ if this.SUM_TIMER_WAIT >= other.SUM_TIMER_WAIT {
+ this.SUM_TIMER_WAIT -= other.SUM_TIMER_WAIT
+ this.COUNT_STAR -= other.COUNT_STAR
+ } else {
+ lib.Logger.Println("WARNING: events_waits_summary_global_by_event_name_row.subtract() - subtraction problem! (not subtracting)")
+ lib.Logger.Println("this=", this)
+ lib.Logger.Println("other=", other)
+ }
+}
+
+func (t events_waits_summary_global_by_event_name_rows) totals() events_waits_summary_global_by_event_name_row {
+ var totals events_waits_summary_global_by_event_name_row
+ totals.EVENT_NAME = "Totals"
+
+ for i := range t {
+ totals.add(t[i])
+ }
+
+ return totals
+}
+
+func select_tiwsbt_rows(dbh *sql.DB) events_waits_summary_global_by_event_name_rows {
+ var t events_waits_summary_global_by_event_name_rows
+
+ // we collect all information even if it's mainly empty as we may reference it later
+ sql := "SELECT EVENT_NAME, SUM_TIMER_WAIT, COUNT_STAR FROM events_waits_summary_global_by_event_name WHERE SUM_TIMER_WAIT > 0 AND EVENT_NAME LIKE 'wait/synch/mutex/innodb/%'"
+
+ rows, err := dbh.Query(sql)
+ if err != nil {
+ log.Fatal(err)
+ }
+ defer rows.Close()
+
+ for rows.Next() {
+ var r events_waits_summary_global_by_event_name_row
+ if err := rows.Scan(
+ &r.EVENT_NAME,
+ &r.SUM_TIMER_WAIT,
+ &r.COUNT_STAR); err != nil {
+ log.Fatal(err)
+ }
+ // we collect all information even if it's mainly empty as we may reference it later
+ t = append(t, r)
+ }
+ if err := rows.Err(); err != nil {
+ log.Fatal(err)
+ }
+
+ return t
+}
+
+func (t events_waits_summary_global_by_event_name_rows) Len() int { return len(t) }
+func (t events_waits_summary_global_by_event_name_rows) Swap(i, j int) { t[i], t[j] = t[j], t[i] }
+
+// sort by value (descending) but also by "name" (ascending) if the values are the same
+func (t events_waits_summary_global_by_event_name_rows) Less(i, j int) bool {
+ return t[i].SUM_TIMER_WAIT > t[j].SUM_TIMER_WAIT
+}
+
+func (t events_waits_summary_global_by_event_name_rows) Sort() {
+ sort.Sort(t)
+}
+
+// remove the initial values from those rows where there's a match
+// - if we find a row we can't match ignore it
+func (this *events_waits_summary_global_by_event_name_rows) subtract(initial events_waits_summary_global_by_event_name_rows) {
+ initial_by_name := make(map[string]int)
+
+ // iterate over rows by name
+ for i := range initial {
+ initial_by_name[initial[i].name()] = i
+ }
+
+ for i := range *this {
+ this_name := (*this)[i].name()
+ if _, ok := initial_by_name[this_name]; ok {
+ initial_index := initial_by_name[this_name]
+ (*this)[i].subtract(initial[initial_index])
+ }
+ }
+}
+
+// if the data in t2 is "newer", "has more values" than t then it needs refreshing.
+// check this by comparing totals.
+func (t events_waits_summary_global_by_event_name_rows) needs_refresh(t2 events_waits_summary_global_by_event_name_rows) bool {
+ my_totals := t.totals()
+ t2_totals := t2.totals()
+
+ return my_totals.SUM_TIMER_WAIT > t2_totals.SUM_TIMER_WAIT
+}
+
+// describe a whole row
+func (r events_waits_summary_global_by_event_name_row) String() string {
+ return fmt.Sprintf("%-30s|%10s %10s %10s %10s %10s|%10s %10s|%10s %10s %10s %10s %10s|%10s %10s",
+ r.pretty_name(),
+ lib.FormatTime(r.SUM_TIMER_WAIT),
+ lib.FormatAmount(r.COUNT_STAR))
+}
+
+// describe a whole table
+func (t events_waits_summary_global_by_event_name_rows) String() string {
+ s := make([]string, len(t))
+
+ for i := range t {
+ s = append(s, t[i].String())
+ }
+
+ return strings.Join(s, "\n")
+}
git://git.iain.cx/iain / pstop.git / blobdiff