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mysql.go
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mysql.go
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// Package mysql parses the mysql slow query log
package mysql
import (
"database/sql"
"fmt"
"math/rand"
"regexp"
"strconv"
"strings"
"sync"
"time"
_ "github.com/go-sql-driver/mysql"
"github.com/honeycombio/mysqltools/query/normalizer"
"github.com/sirupsen/logrus"
"github.com/honeycombio/honeytail/event"
"github.com/honeycombio/honeytail/httime"
"github.com/honeycombio/honeytail/parsers"
)
// See mysql_test for example log entries
// 3 sample log entries
//
// # Time: 2016-04-01T00:31:09.817887Z
// # User@Host: root[root] @ localhost [] Id: 233
// # Query_time: 0.008393 Lock_time: 0.000154 Rows_sent: 1 Rows_examined: 357
// SET timestamp=1459470669;
// show status like 'Uptime';
//
// # Time: 2016-04-01T00:31:09.853523Z
// # User@Host: root[root] @ localhost [] Id: 233
// # Query_time: 0.020424 Lock_time: 0.000147 Rows_sent: 494 Rows_examined: 494
// SET timestamp=1459470669;
// SHOW /*innotop*/ GLOBAL VARIABLES;
//
// # Time: 2016-04-01T00:31:09.856726Z
// # User@Host: root[root] @ localhost [] Id: 233
// # Query_time: 0.000021 Lock_time: 0.000000 Rows_sent: 494 Rows_examined: 494
// SET timestamp=1459470669;
// # administrator command: Ping;
//
// We should ignore the administrator command entry; the stats it presents (eg rows_sent)
// are actually for the previous command
//
// Sample line from RDS
// # administrator command: Prepare;
// # User@Host: root[root] @ [10.0.1.76] Id: 325920
// # Query_time: 0.000097 Lock_time: 0.000023 Rows_sent: 1 Rows_examined: 1
// SET timestamp=1476127288;
// SELECT * FROM foo WHERE bar=2 AND (baz=104 OR baz=0) ORDER BY baz;
const (
rdsStr = "rds"
ec2Str = "ec2"
selfStr = "self"
// Event attributes
userKey = "user"
clientKey = "client"
queryTimeKey = "query_time"
lockTimeKey = "lock_time"
rowsSentKey = "rows_sent"
rowsExaminedKey = "rows_examined"
rowsAffectedKey = "rows_affected"
databaseKey = "database"
queryKey = "query"
normalizedQueryKey = "normalized_query"
statementKey = "statement"
tablesKey = "tables"
commentsKey = "comments"
// InnoDB keys (it seems)
bytesSentKey = "bytes_sent"
tmpTablesKey = "tmp_tables"
tmpDiskTablesKey = "tmp_disk_tables"
tmpTableSizesKey = "tmp_table_sizes"
transactionIDKey = "transaction_id"
queryCacheHitKey = "query_cache_hit"
fullScanKey = "full_scan"
fullJoinKey = "full_join"
tmpTableKey = "tmp_table"
tmpTableOnDiskKey = "tmp_table_on_disk"
fileSortKey = "filesort"
fileSortOnDiskKey = "filesort_on_disk"
mergePassesKey = "merge_passes"
ioROpsKey = "IO_r_ops"
ioRBytesKey = "IO_r_bytes"
ioRWaitKey = "IO_r_wait_sec"
recLockWaitKey = "rec_lock_wait_sec"
queueWaitKey = "queue_wait_sec"
pagesDistinctKey = "pages_distinct"
// Event attributes that apply to the host as a whole
hostedOnKey = "hosted_on"
readOnlyKey = "read_only"
replicaLagKey = "replica_lag"
roleKey = "role"
)
var (
reTime = parsers.ExtRegexp{regexp.MustCompile("^# Time: (?P<time>[^ ]+)Z *$")}
// older versions of the mysql slow query log use this format for the timestamp
reOldTime = parsers.ExtRegexp{regexp.MustCompile("^# Time: (?P<datetime>[0-9]+ [0-9:.]+)")}
reAdminPing = parsers.ExtRegexp{regexp.MustCompile("^# administrator command: Ping; *$")}
reUser = parsers.ExtRegexp{regexp.MustCompile("^# User@Host: (?P<user>[^#]+) @ (?P<host>[^#]+?)( Id:.+)?$")}
reQueryStats = parsers.ExtRegexp{regexp.MustCompile("^# Query_time: (?P<queryTime>[0-9.]+) *Lock_time: (?P<lockTime>[0-9.]+) *Rows_sent: (?P<rowsSent>[0-9]+) *Rows_examined: (?P<rowsExamined>[0-9]+)( *Rows_affected: (?P<rowsAffected>[0-9]+))?.*$")}
// when capturing the log from the wire, you don't get lock time etc., only query time
reTCPQueryStats = parsers.ExtRegexp{regexp.MustCompile("^# Query_time: (?P<queryTime>[0-9.]+).*$")}
reServStats = parsers.ExtRegexp{regexp.MustCompile("^# Bytes_sent: (?P<bytesSent>[0-9.]+) *Tmp_tables: (?P<tmpTables>[0-9.]+) *Tmp_disk_tables: (?P<tmpDiskTables>[0-9]+) *Tmp_table_sizes: (?P<tmpTableSizes>[0-9]+).*$")}
reInnodbTrx = parsers.ExtRegexp{regexp.MustCompile("^# InnoDB_trx_id: (?P<trxId>[A-F0-9]+) *$")}
reInnodbQueryPlan1 = parsers.ExtRegexp{regexp.MustCompile("^# QC_Hit: (?P<query_cache_hit>[[:alpha:]]+) Full_scan: (?P<full_scan>[[:alpha:]]+) Full_join: (?P<full_join>[[:alpha:]]+) Tmp_table: (?P<tmp_table>[[:alpha:]]+) Tmp_table_on_disk: (?P<tmp_table_on_disk>[[:alpha:]]+).*$")}
reInnodbQueryPlan2 = parsers.ExtRegexp{regexp.MustCompile("^# Filesort: (?P<filesort>[[:alpha:]]+) Filesort_on_disk: (?P<filesort_on_disk>[[:alpha:]]+) Merge_passes: (?P<merge_passes>[0-9]+).*$")}
reInnodbUsage1 = parsers.ExtRegexp{regexp.MustCompile("^# +InnoDB_IO_r_ops: (?P<io_r_ops>[0-9]+) InnoDB_IO_r_bytes: (?P<io_r_bytes>[0-9]+) InnoDB_IO_r_wait: (?P<io_r_wait>[0-9.]+).*$")}
reInnodbUsage2 = parsers.ExtRegexp{regexp.MustCompile("^# +InnoDB_rec_lock_wait: (?P<rec_lock_wait>[0-9.]+) InnoDB_queue_wait: (?P<queue_wait>[0-9.]+).*$")}
reInnodbUsage3 = parsers.ExtRegexp{regexp.MustCompile("^# +InnoDB_pages_distinct: (?P<pages_distinct>[0-9]+).*")}
reSetTime = parsers.ExtRegexp{regexp.MustCompile("^SET timestamp=(?P<unixTime>[0-9]+);$")}
reUse = parsers.ExtRegexp{regexp.MustCompile("^(?i)use ")}
// if 'flush logs' is run at the mysql prompt (which rds commonly does, apparently) the following shows up in slow query log:
// /usr/local/Cellar/mysql/5.7.12/bin/mysqld, Version: 5.7.12 (Homebrew). started with:
// Tcp port: 3306 Unix socket: /tmp/mysql.sock
// Time Id Command Argument
reMySQLVersion = parsers.ExtRegexp{regexp.MustCompile("/.*, Version: .* .*MySQL Community Server.*")}
reMySQLPortSock = parsers.ExtRegexp{regexp.MustCompile("Tcp port:.* Unix socket:.*")}
reMySQLColumnHeaders = parsers.ExtRegexp{regexp.MustCompile("Time.*Id.*Command.*Argument.*")}
)
const timeFormat = "2006-01-02T15:04:05.000000"
const oldTimeFormat = "010206 15:04:05.999999"
type Options struct {
Host string `long:"host" description:"MySQL host in the format (address:port)"`
User string `long:"user" description:"MySQL username"`
Pass string `long:"pass" description:"MySQL password"`
QueryInterval uint `long:"interval" description:"interval for querying the MySQL DB in seconds"`
NumParsers int `hidden:"true" description:"number of MySQL parsers to spin up" yaml:"-"`
}
type Parser struct {
// set SampleRate to cause the MySQL parser to drop events after before
// they're parsed to save CPU
SampleRate int
conf Options
wg sync.WaitGroup
hostedOn string
readOnly *bool
replicaLag *int64
role *string
}
// the normalizer can't be shared by all threads.
type perThreadParser struct {
normalizer *normalizer.Parser
}
func (p *Parser) Init(options interface{}) error {
p.conf = *options.(*Options)
if p.conf.Host != "" {
url := fmt.Sprintf("%s:%s@tcp(%s)/", p.conf.User, p.conf.Pass, p.conf.Host)
db, err := sql.Open("mysql", url)
if err != nil {
logrus.Fatal(err)
}
// run one time queries
hostedOn, err := getHostedOn(db)
if err != nil {
logrus.WithError(err).Warn("failed to get host env")
}
p.hostedOn = hostedOn
role, err := getRole(db)
if err != nil {
logrus.WithError(err).Warn("failed to get role")
}
p.role = role
// update hostedOn and readOnly every <n> seconds
queryInterval := p.conf.QueryInterval
if queryInterval == 0 {
queryInterval = 30
}
go func() {
defer db.Close()
ticker := time.NewTicker(time.Second * time.Duration(queryInterval))
for _ = range ticker.C {
readOnly, err := getReadOnly(db)
if err != nil {
logrus.WithError(err).Warn("failed to get read-only state")
}
p.readOnly = readOnly
replicaLag, err := getReplicaLag(db)
if err != nil {
logrus.WithError(err).Warn("failed to get replica lag")
}
p.replicaLag = replicaLag
}
}()
}
return nil
}
func getReadOnly(db *sql.DB) (*bool, error) {
rows, err := db.Query("SELECT @@global.read_only;")
if err != nil {
return nil, err
}
defer rows.Close()
var value bool
rows.Next()
if err := rows.Scan(&value); err != nil {
logrus.WithError(err).Warn("failed to get read-only state")
return nil, err
}
if err := rows.Err(); err != nil {
logrus.WithError(err).Warn("failed to get read-only state")
return nil, err
}
return &value, nil
}
func getHostedOn(db *sql.DB) (string, error) {
rows, err := db.Query("SHOW GLOBAL VARIABLES WHERE Variable_name = 'basedir';")
if err != nil {
return "", err
}
defer rows.Close()
var varName, value string
for rows.Next() {
if err := rows.Scan(&varName, &value); err != nil {
return "", err
}
if strings.HasPrefix(value, "/rdsdbbin/") {
return rdsStr, nil
}
}
// TODO: implement ec2 detection
if err := rows.Err(); err != nil {
return "", err
}
return "", nil
}
func getReplicaLag(db *sql.DB) (*int64, error) {
rows, err := db.Query("SHOW SLAVE STATUS")
if err != nil {
return nil, err
}
defer rows.Close()
if !rows.Next() {
return nil, err
}
columns, _ := rows.Columns()
values := make([]interface{}, len(columns))
for i := range values {
var v sql.RawBytes
values[i] = &v
}
err = rows.Scan(values...)
if err != nil {
return nil, err
}
for i, name := range columns {
bp := values[i].(*sql.RawBytes)
vs := string(*bp)
if name == "Seconds_Behind_Master" {
vi, err := strconv.ParseInt(vs, 10, 64)
if err != nil {
return nil, err
}
return &vi, nil
}
}
return nil, nil
}
func getRole(db *sql.DB) (*string, error) {
var res string
rows, err := db.Query("SHOW MASTER STATUS")
if err != nil {
return nil, err
}
defer rows.Close()
if !rows.Next() {
res = "secondary"
return nil, err
}
res = "primary"
return &res, nil
}
func isMySQLHeaderLine(line string) bool {
if len(line) == 0 {
return false
}
first := line[0]
return (first == '/' && reMySQLVersion.MatchString(line)) ||
(first == 'T' && reMySQLPortSock.MatchString(line)) ||
(first == 'T' && reMySQLColumnHeaders.MatchString(line))
}
func (p *Parser) ProcessLines(lines <-chan string, send chan<- event.Event, prefixRegex *parsers.ExtRegexp) {
// start up a goroutine to handle grouped sets of lines
rawEvents := make(chan []string)
defer p.wg.Wait()
p.wg.Add(1)
go p.handleEvents(rawEvents, send)
// flag to indicate when we've got a complete event to send
var foundStatement bool
groupedLines := make([]string, 0, 5)
for line := range lines {
line = strings.TrimSpace(line)
// mysql parser does not support capturing fields in the line prefix - just
// strip it.
if prefixRegex != nil {
var prefix string
prefix = prefixRegex.FindString(line)
line = strings.TrimPrefix(line, prefix)
}
lineIsComment := strings.HasPrefix(line, "# ")
if !lineIsComment && !isMySQLHeaderLine(line) {
// we've finished the comments before the statement and now should slurp
// lines until the next comment
foundStatement = true
} else {
if foundStatement {
// we've started a new event. Send the previous one.
foundStatement = false
// if sampling is disabled or sampler says keep, pass along this group.
if p.SampleRate <= 1 || rand.Intn(p.SampleRate) == 0 {
rawEvents <- groupedLines
}
groupedLines = make([]string, 0, 5)
}
}
groupedLines = append(groupedLines, line)
}
// send the last event, if there was one collected
if foundStatement {
// if sampling is disabled or sampler says keep, pass along this group.
if p.SampleRate <= 1 || rand.Intn(p.SampleRate) == 0 {
rawEvents <- groupedLines
}
}
logrus.Debug("lines channel is closed, ending mysql processor")
close(rawEvents)
}
func (p *Parser) handleEvents(rawEvents <-chan []string, send chan<- event.Event) {
defer p.wg.Done()
wg := sync.WaitGroup{}
numParsers := 1
if p.conf.NumParsers > 0 {
numParsers = p.conf.NumParsers
}
for i := 0; i < numParsers; i++ {
ptp := perThreadParser{
normalizer: &normalizer.Parser{},
}
wg.Add(1)
go func() {
for rawE := range rawEvents {
sq, timestamp := p.handleEvent(&ptp, rawE)
if len(sq) == 0 {
continue
}
if q, ok := sq["query"]; !ok || q == "" {
// skip events with no query field
continue
}
if p.hostedOn != "" {
sq[hostedOnKey] = p.hostedOn
}
if p.readOnly != nil {
sq[readOnlyKey] = *p.readOnly
}
if p.replicaLag != nil {
sq[replicaLagKey] = *p.replicaLag
}
if p.role != nil {
sq[roleKey] = *p.role
}
send <- event.Event{
Timestamp: timestamp,
SampleRate: p.SampleRate,
Data: sq,
}
}
wg.Done()
}()
}
wg.Wait()
logrus.Debug("done with mysql handleEvents")
}
// Parse a set of MySQL log lines that seem to represent a single event and
// return a struct of extracted data as well as the highest-resolution timestamp
// available.
func (p *Parser) handleEvent(ptp *perThreadParser, rawE []string) (
map[string]interface{}, time.Time) {
sq := map[string]interface{}{}
if len(rawE) == 0 {
return sq, time.Time{}
}
var (
timeFromComment time.Time
timeFromSet int64
query = ""
)
for _, line := range rawE {
// parse each line and populate the map of attributes
if _, mg := reTime.FindStringSubmatchMap(line); mg != nil {
timeFromComment, _ = httime.Parse(timeFormat, mg["time"])
} else if _, mg := reOldTime.FindStringSubmatchMap(line); mg != nil {
timeFromComment, _ = httime.Parse(oldTimeFormat, mg["datetime"])
} else if reAdminPing.MatchString(line) {
// this event is an administrative ping and we should
// ignore the entire event
logrus.WithFields(logrus.Fields{
"line": line,
"event": rawE,
}).Debug("readmin ping detected; skipping this event")
return nil, time.Time{}
} else if _, mg := reUser.FindStringSubmatchMap(line); mg != nil {
query = ""
sq[userKey] = strings.Split(mg["user"], "[")[0]
sq[clientKey] = strings.TrimSpace(mg["host"])
} else if _, mg := reQueryStats.FindStringSubmatchMap(line); mg != nil {
query = ""
if queryTime, err := strconv.ParseFloat(mg["queryTime"], 64); err == nil {
sq[queryTimeKey] = queryTime
}
if lockTime, err := strconv.ParseFloat(mg["lockTime"], 64); err == nil {
sq[lockTimeKey] = lockTime
}
if rowsSent, err := strconv.Atoi(mg["rowsSent"]); err == nil {
sq[rowsSentKey] = rowsSent
}
if rowsExamined, err := strconv.Atoi(mg["rowsExamined"]); err == nil {
sq[rowsExaminedKey] = rowsExamined
}
if rowsAffected, err := strconv.Atoi(mg["rowsAffected"]); err == nil {
sq[rowsAffectedKey] = rowsAffected
}
} else if _, mg := reTCPQueryStats.FindStringSubmatchMap(line); mg != nil {
query = ""
if queryTime, err := strconv.ParseFloat(mg["queryTime"], 64); err == nil {
sq[queryTimeKey] = queryTime
}
} else if _, mg := reServStats.FindStringSubmatchMap(line); mg != nil {
query = ""
if bytesSent, err := strconv.Atoi(mg["bytesSent"]); err == nil {
sq[bytesSentKey] = bytesSent
}
if tmpTables, err := strconv.Atoi(mg["tmpTables"]); err == nil {
sq[tmpTablesKey] = tmpTables
}
if tmpDiskTables, err := strconv.Atoi(mg["tmpDiskTables"]); err == nil {
sq[tmpDiskTablesKey] = tmpDiskTables
}
if tmpTableSizes, err := strconv.Atoi(mg["tmpTableSizes"]); err == nil {
sq[tmpTableSizesKey] = tmpTableSizes
}
} else if _, mg := reInnodbQueryPlan1.FindStringSubmatchMap(line); mg != nil {
sq[queryCacheHitKey] = mg["query_cache_hit"] == "Yes"
sq[fullScanKey] = mg["full_scan"] == "Yes"
sq[fullJoinKey] = mg["full_join"] == "Yes"
sq[tmpTableKey] = mg["tmp_table"] == "Yes"
sq[tmpTableOnDiskKey] = mg["tmp_table_on_disk"] == "Yes"
} else if _, mg := reInnodbQueryPlan2.FindStringSubmatchMap(line); mg != nil {
sq[fileSortKey] = mg["filesort"] == "Yes"
sq[fileSortOnDiskKey] = mg["filesort_on_disk"] == "Yes"
if mergePasses, err := strconv.Atoi(mg["merge_passes"]); err == nil {
sq[mergePassesKey] = mergePasses
}
} else if _, mg := reInnodbUsage1.FindStringSubmatchMap(line); mg != nil {
if ioROps, err := strconv.Atoi(mg["io_r_ops"]); err == nil {
sq[ioROpsKey] = ioROps
}
if ioRBytes, err := strconv.Atoi(mg["io_r_bytes"]); err == nil {
sq[ioRBytesKey] = ioRBytes
}
if ioRWait, err := strconv.ParseFloat(mg["io_r_wait"], 64); err == nil {
sq[ioRWaitKey] = ioRWait
}
} else if _, mg := reInnodbUsage2.FindStringSubmatchMap(line); mg != nil {
if recLockWait, err := strconv.ParseFloat(mg["rec_lock_wait"], 64); err == nil {
sq[recLockWaitKey] = recLockWait
}
if queueWait, err := strconv.ParseFloat(mg["queue_wait"], 64); err == nil {
sq[queueWaitKey] = queueWait
}
} else if _, mg := reInnodbUsage3.FindStringSubmatchMap(line); mg != nil {
if pagesDistinct, err := strconv.Atoi(mg["pages_distinct"]); err == nil {
sq[pagesDistinctKey] = pagesDistinct
}
} else if _, mg := reInnodbTrx.FindStringSubmatchMap(line); mg != nil {
sq[transactionIDKey] = mg["trxId"]
} else if match := reUse.FindString(line); match != "" {
query = ""
db := strings.TrimPrefix(line, match)
db = strings.TrimRight(db, ";")
db = strings.Trim(db, "`")
sq[databaseKey] = db
// Use this line as the query/normalized_query unless, if a real query follows it will be replaced.
sq[queryKey] = strings.TrimRight(line, ";")
sq[normalizedQueryKey] = sq[queryKey]
} else if _, mg := reSetTime.FindStringSubmatchMap(line); mg != nil {
query = ""
timeFromSet, _ = strconv.ParseInt(mg["unixTime"], 10, 64)
} else if isMySQLHeaderLine(line) {
// ignore and skip the header lines
} else if !strings.HasPrefix(line, "# ") {
// treat any other line that doesn't start with '# ' as part of the
// query
query = query + " " + line
if strings.HasSuffix(query, ";") {
q := strings.TrimSpace(strings.TrimSuffix(query, ";"))
sq[queryKey] = q
sq[normalizedQueryKey] = ptp.normalizer.NormalizeQuery(q)
if len(ptp.normalizer.LastTables) > 0 {
sq[tablesKey] = strings.Join(ptp.normalizer.LastTables, " ")
}
if len(ptp.normalizer.LastComments) > 0 {
sq[commentsKey] = "/* " + strings.Join(ptp.normalizer.LastComments, " */ /* ") + " */"
}
sq[statementKey] = ptp.normalizer.LastStatement
query = ""
}
} else {
// unknown row; log and skip
logrus.WithFields(logrus.Fields{
"line": line,
}).Debug("No regex match for line in the middle of a query. skipping")
}
}
// We always need a timestamp.
//
// timeFromComment may include millisecond resolution but doesn't include
// time zone.
// timeFromSet is a UNIX timestamp and thus more reliable, but also (thus)
// doesn't contain millisecond resolution.
//
// In the best case (we have both), we combine the two; in the worst case (we
// have neither) we fall back to "now."
combinedTime := httime.Now()
if !timeFromComment.IsZero() && timeFromSet > 0 {
nanos := time.Duration(timeFromComment.Nanosecond())
combinedTime = time.Unix(timeFromSet, 0).Add(nanos)
} else if !timeFromComment.IsZero() {
combinedTime = timeFromComment // cross our fingers that UTC is ok
} else if timeFromSet > 0 {
combinedTime = time.Unix(timeFromSet, 0)
}
return sq, combinedTime
}
// custom error to indicate empty query
type emptyQueryError struct {
err string
}
func (e *emptyQueryError) Error() string {
e.err = "skipped slow query"
return e.err
}