问使用RXJS的并行请求会对性能有更好的影响吗？

EN

from(observableQueries)
           .pipe(
               mergeMap(partialQuery => this.messageService.getResults(partialQuery, true), 4),
               takeWhile(o => {
                   if (!o.isMoreResults && o.auditMessageList.length === 0) {
                       this.logger.log(`First page that returns false ${ o.number }`);
                       this.logger.log(`Count of responses that exists in array: ${ allResults.length }`);
                       if (!firstPageThatShouldBeStopped) {
                           firstPageThatShouldBeStopped = o.number;
                       }

                       if (allResults.length === firstPageThatShouldBeStopped) {
                           return false;
                       }
                   }
                   return true;
               }),
               retryWhen(genericRetryStrategy()),
               catchError((err, caught) => {
                   this._alertService.error(this._translate.instant('EXPORT_TO_CSV_DOWNLOAD_ERROR'));
                   return throwError(err);
               })
           )
           .subscribe(
               (res: MessagesResult) => {
                   if (reThrowError) {
                       this.logger.info('Error will be thrown for e2e purposes');
                       throw new Error('Error will throw for e2e purposes');
                   }
                   if (res.isMoreResults && res.auditMessageList.length > 0) {
                       allResults[res.number] = res;
                       this.subject.next(true);
                   } else if (!res.isMoreResults && res.auditMessageList.length > 0) {
                       allResults[res.number] = res;
                       this.subject.next(true);
                   } else {
                       this.subject.next(false);
                   }
               },
               err => {
                   // clear subject after emitting value...
                   this.subject.next(true);
                   return this.handleError(err);
               },
               () => {
                   this.logger.info('Download file finished...');
                   this.logger.info('Time consumed: ', performance.now() - start);
                   try {
                       this.logger.info(`Count Responses: ${ allResults.length } `);
                       const allResultSorted = this._sortResults(allResults);
                       let counter = 0;
                       for (let i = 0; i < allResultSorted.length; i++) {
                           this.logger.info('Index: ' + i, allResultSorted[i]);
                           counter += allResultSorted[i].auditMessageList.length;
                           this.logger.info('Length OF Messages: ' + i, counter);
                           this.fileSaver.save(!allResultSorted[i].isMoreResults, allResultSorted[i].auditMessageList,
                               `audit-events_${ LOCAL_QUERY_COPY.application }_${ timestamp }_${ moment()
                                   .tz(this._timezoneService.timezone).zoneName() }.csv`, null, headers);
                       }
                       this.subject.next(false);
                   } catch (e) {
                       this._alertService.error(this._translate.instant('EXPORT_TO_CSV_DOWNLOAD_ERROR'));
                       return this.handleError(e);
                   } finally {
                       // clear subject after emitting value...
                       this.subject.next(true);
                   }
               }
           );