src/vs/platform/log/common/fileLog.ts/FileLogger/_log
class FileLogger:	private _log(level: LogLevel, message: string): void {
		this.queue.queue(async () => {
			await this.initializePromise;
			let content = await this.loadContent();
			if (content.length > MAX_FILE_SIZE) {
				await this.fileService.writeFile(this.getBackupResource(), VSBuffer.fromString(content));
				content = '';
			}
			content += `[${this.getCurrentTimestamp()}] [${this.name}] [${this.stringifyLogLevel(level)}] ${message}\n`;
			await this.fileService.writeFile(this.resource, VSBuffer.fromString(content));
		});
	}