fix(server): compress database backups on 75% of the cores, up to 32 (#32823)

(cherry picked from commit 02c0d4d392217b02b670afb0b4ce9941330120ec)

server/src/services/database-backup.service.spec.ts

@@ -241,11 +241,19 @@ describe(DatabaseBackupService.name, () => {
       expect(mocks.process.spawnDuplexStream).toHaveBeenLastCalledWith('gzip', ['--rsyncable']);
     });
 
-    it('should compress with pigz on every available core when it is installed', async () => {
+    it.each([
+      { cores: 1, processes: '1' },
+      { cores: 8, processes: '6' },
+      { cores: 72, processes: '32' },
+    ])('should compress with pigz on $processes of $cores cores when it is installed', async ({ cores, processes }) => {
       mocks.process.isCommandAvailable.mockResolvedValue(true);
-      mocks.process.availableParallelism.mockReturnValue(8);
+      mocks.process.availableParallelism.mockReturnValue(cores);
       await sut.handleBackupDatabase();
-      expect(mocks.process.spawnDuplexStream).toHaveBeenLastCalledWith('pigz', ['--rsyncable', '--processes', '8']);
+      expect(mocks.process.spawnDuplexStream).toHaveBeenLastCalledWith('pigz', [
+        '--rsyncable',
+        '--processes',
+        processes,
+      ]);
     });
 
     it('should fail if pg_dump fails', async () => {

server/src/services/database-backup.service.ts

@@ -271,7 +271,7 @@ export class DatabaseBackupService {
 
   private async getCompressionCommand() {
     if (await this.processRepository.isCommandAvailable('pigz')) {
-      const processes = this.processRepository.availableParallelism();
+      const processes = Math.min(Math.max(Math.floor(this.processRepository.availableParallelism() * 0.75), 1), 32);
       return { command: 'pigz', args: ['--rsyncable', '--processes', processes.toString()] };
     }