Massive speedup in job table initialization

It went from taking like 15 minutes on a ramdisk to taking 430 seconds
on my SSD (~900000 jobs inserted).

- Create indexes after inserts so that they do not need to be updated continually
- Use prepared statements for the job insert
- Bundle 200 job inserts into a single transaction

init-db.go

@@ -4,14 +4,20 @@ import (
 	"bufio"
 	"database/sql"
 	"encoding/json"
-	"github.com/jmoiron/sqlx"
+	"fmt"
-	"log"
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
+
+	"github.com/jmoiron/sqlx"
 )
 
 func initDB(db *sqlx.DB, archive string) error {
+	starttime := time.Now()
+	fmt.Println("Building database...")
+
+	// Basic database structure:
 	_, err := db.Exec(`
 	DROP TABLE IF EXISTS job;
 	DROP TABLE IF EXISTS tag;
@@ -44,10 +50,7 @@ func initDB(db *sqlx.DB, archive string) error {
 		tag_id INTEGER,
 		PRIMARY KEY (job_id, tag_id),
 		FOREIGN KEY (job_id) REFERENCES job (id) ON DELETE CASCADE ON UPDATE NO ACTION,
-		FOREIGN KEY (tag_id) REFERENCES tag (id) ON DELETE CASCADE ON UPDATE NO ACTION);
+		FOREIGN KEY (tag_id) REFERENCES tag (id) ON DELETE CASCADE ON UPDATE NO ACTION);`)
-
-	CREATE INDEX job_by_user ON job (user_id);
-	CREATE INDEX job_by_starttime ON job (start_time);`)
 	if err != nil {
 		return err
 	}
@@ -57,6 +60,15 @@ func initDB(db *sqlx.DB, archive string) error {
 		return err
 	}
 
+	insertstmt, err := db.Prepare(`INSERT INTO job
+		(job_id, user_id, project_id, cluster_id, start_time, duration, job_state, num_nodes, node_list, metadata, flops_any_avg, mem_bw_avg, net_bw_avg, file_bw_avg, load_avg)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`)
+	if err != nil {
+		return err
+	}
+
+	var tx *sql.Tx = nil
+	var i int = 0
 	tags := make(map[string]int64)
 	for _, entry0 := range entries0 {
 		entries1, err := os.ReadDir(filepath.Join(archive, entry0.Name()))
@@ -75,13 +87,45 @@ func initDB(db *sqlx.DB, archive string) error {
 			}
 
 			for _, entry2 := range entries2 {
-				if err = loadJob(db, tags, filepath.Join(archive, entry0.Name(), entry1.Name(), entry2.Name())); err != nil {
+				// Bundle 200 inserts into one transaction for better performance:
+				if i%200 == 0 {
+					if tx != nil {
+						if err := tx.Commit(); err != nil {
 							return err
 						}
 					}
+
+					tx, err = db.Begin()
+					if err != nil {
+						return err
+					}
+
+					insertstmt = tx.Stmt(insertstmt)
+					fmt.Printf("%d jobs inserted...\r", i)
+				}
+
+				if err = loadJob(tx, insertstmt, tags, filepath.Join(archive, entry0.Name(), entry1.Name(), entry2.Name())); err != nil {
+					return err
+				}
+
+				i += 1
+			}
 		}
 	}
 
+	if err := tx.Commit(); err != nil {
+		return err
+	}
+
+	// Create indexes after inserts so that they do not
+	// need to be continually updated.
+	if _, err := db.Exec(`
+		CREATE INDEX job_by_user ON job (user_id);
+		CREATE INDEX job_by_starttime ON job (start_time);`); err != nil {
+		return err
+	}
+
+	fmt.Printf("A total of %d jobs have been registered in %.3f seconds.\n", i, time.Since(starttime).Seconds())
 	return nil
 }
 
@@ -107,7 +151,7 @@ type JobMetaFile struct {
 	} `json:"statistics"`
 }
 
-func loadJob(db *sqlx.DB, tags map[string]int64, path string) error {
+func loadJob(tx *sql.Tx, stmt *sql.Stmt, tags map[string]int64, path string) error {
 	f, err := os.Open(filepath.Join(path, "meta.json"))
 	if err != nil {
 		return err
@@ -125,14 +169,8 @@ func loadJob(db *sqlx.DB, tags map[string]int64, path string) error {
 	fileBwAvg := loadJobStat(&job, "file_bw")
 	loadAvg := loadJobStat(&job, "load_one")
 
-	res, err := db.Exec(`
+	res, err := stmt.Exec(job.JobId, job.UserId, job.ProjectId, job.ClusterId, job.StartTime, job.Duration, job.JobState,
-		INSERT INTO job
+		job.NumNodes, strings.Join(job.Nodes, ","), nil, flopsAnyAvg, memBwAvg, netBwAvg, fileBwAvg, loadAvg)
-			(job_id, user_id, project_id, cluster_id, start_time, duration, job_state, num_nodes, node_list, metadata,
-			flops_any_avg, mem_bw_avg, net_bw_avg, file_bw_avg, load_avg)
-		VALUES
-			(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?);`,
-		job.JobId, job.UserId, job.ProjectId, job.ClusterId, job.StartTime, job.Duration, job.JobState, job.NumNodes, strings.Join(job.Nodes, ","), nil,
-		flopsAnyAvg, memBwAvg, netBwAvg, fileBwAvg, loadAvg)
 	if err != nil {
 		return err
 	}
@@ -142,15 +180,11 @@ func loadJob(db *sqlx.DB, tags map[string]int64, path string) error {
 		return err
 	}
 
-	if id % 50 == 0 {
-		log.Printf("Inserting Job (id: %d, jobId: %s, clusterId: %s)\n", id, job.JobId, job.ClusterId)
-	}
-
 	for _, tag := range job.Tags {
 		tagstr := tag.Name + ":" + tag.Type
 		tagId, ok := tags[tagstr]
 		if !ok {
-			res, err := db.Exec(`INSERT INTO tag (tag_name, tag_type) VALUES (?, ?)`, tag.Name, tag.Type)
+			res, err := tx.Exec(`INSERT INTO tag (tag_name, tag_type) VALUES (?, ?)`, tag.Name, tag.Type)
 			if err != nil {
 				return err
 			}
@@ -161,7 +195,7 @@ func loadJob(db *sqlx.DB, tags map[string]int64, path string) error {
 			tags[tagstr] = tagId
 		}
 
-		if _, err := db.Exec(`INSERT INTO jobtag (job_id, tag_id) VALUES (?, ?)`, id, tagId); err != nil {
+		if _, err := tx.Exec(`INSERT INTO jobtag (job_id, tag_id) VALUES (?, ?)`, id, tagId); err != nil {
 			return err
 		}
 	}