fix: only update job state fields during job processing

this improves performance

src/Job.ts

@@ -282,7 +282,8 @@ export class Job<DATA = unknown | void> {
 		}
 		this.attrs.lockedAt = new Date();
 		this.attrs.progress = progress;
-		await this.save();
+
+		await this.agenda.db.saveJobState(this);
 	}
 
 	private computeNextRunAt() {
@@ -326,7 +327,7 @@ export class Job<DATA = unknown | void> {
 			this.attrs.lastRunAt.toISOString()
 		);
 		this.computeNextRunAt();
-		await this.save();
+		await this.agenda.db.saveJobState(this);
 
 		try {
 			this.agenda.emit('start', this);
@@ -376,7 +377,7 @@ export class Job<DATA = unknown | void> {
 			log('[%s:%s] has failed [%s]', this.attrs.name, this.attrs._id, error.message);
 		} finally {
 			this.attrs.lockedAt = undefined;
-			await this.save();
+			await this.agenda.db.saveJobState(this);
 			log('[%s:%s] was saved successfully to MongoDB', this.attrs.name, this.attrs._id);
 
 			this.agenda.emit('complete', this);

src/JobDbRepository.ts

@@ -243,6 +243,25 @@ export class JobDbRepository {
 		return job;
 	}
 
+	async saveJobState(job: Job<any>): Promise<void> {
+		await this.collection.updateOne(
+			{ _id: job.attrs._id },
+			{
+				$set: {
+					lockedAt: job.attrs.lockedAt,
+					nextRunAt: (job.attrs.nextRunAt && new Date(job.attrs.nextRunAt)) || undefined,
+					lastRunAt: (job.attrs.lastRunAt && new Date(job.attrs.lastRunAt)) || undefined,
+					progress: job.attrs.progress,
+					failReason: job.attrs.failReason,
+					failCount: job.attrs.failCount,
+					failedAt: job.attrs.failedAt && new Date(job.attrs.failedAt),
+					lastFinishedAt:
+						(job.attrs.lastFinishedAt && new Date(job.attrs.lastFinishedAt)) || undefined
+				}
+			}
+		);
+	}
+
 	/**
 	 * Save the properties on a job to MongoDB
 	 * @name Agenda#saveJob

test/agenda.test.ts

@@ -318,6 +318,8 @@ describe('Agenda', () => {
 						.schedule('now')
 						.save();
 
+					await delay(100);
+
 					const job2 = await globalAgenda
 						.create('unique job', {
 							type: 'active',