Dmitry S d191859be7 (core) For exporting XLSX, do it memory-efficiently in a worker thread. ... Summary: - Excel exports were awfully memory-inefficient, causing occasional docWorker crashes. The fix is to use the "streaming writer" option of ExcelJS https://github.com/exceljs/exceljs#streaming-xlsx-writercontents. (Empirically on one example, max memory went down from 3G to 100M) - It's also CPU intensive and synchronous, and can block node for tens of seconds. The fix is to use a worker-thread. This diff uses "piscina" library for a pool of threads. - Additionally, adds ProcessMonitor that logs memory and cpu usage, particularly when those change significantly. - Also introduces request cancellation, so that a long download cancelled by the user will cancel the work being done in the worker thread. Test Plan: Updated previous export tests; memory and CPU performance tested manually by watching output of ProcessMonitor. Difference visible in these log excerpts: Before (total time to serve request 22 sec): ``` Telemetry processMonitor heapUsedMB=2187, heapTotalMB=2234, cpuAverage=1.13, intervalMs=17911 Telemetry processMonitor heapUsedMB=2188, heapTotalMB=2234, cpuAverage=0.66, intervalMs=5005 Telemetry processMonitor heapUsedMB=2188, heapTotalMB=2234, cpuAverage=0, intervalMs=5005 Telemetry processMonitor heapUsedMB=71, heapTotalMB=75, cpuAverage=0.13, intervalMs=5002 ``` After (total time to server request 18 sec): ``` Telemetry processMonitor heapUsedMB=109, heapTotalMB=144, cpuAverage=0.5, intervalMs=5001 Telemetry processMonitor heapUsedMB=109, heapTotalMB=144, cpuAverage=1.39, intervalMs=5002 Telemetry processMonitor heapUsedMB=94, heapTotalMB=131, cpuAverage=1.13, intervalMs=5000 Telemetry processMonitor heapUsedMB=94, heapTotalMB=131, cpuAverage=1.35, intervalMs=5001 ``` Note in "Before" that heapTotalMB goes up to 2GB in the first case, and "intervalMs" of 17 seconds indicates that node was unresponsive for that long. In the second case, heapTotalMB stays low, and the main thread remains responsive the whole time. Reviewers: jarek Reviewed By: jarek Differential Revision: https://phab.getgrist.com/D3906		2023-06-01 12:06:48 -04:00
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docs	(core) reconcile webhook and widget description migrations	2023-05-15 11:56:15 -04:00
export-csv	(core) Fix imports into reference columns, and support two ways to import Numeric as a reference.	2023-05-02 10:28:14 -04:00
export-xlsx	(core) For exporting XLSX, do it memory-efficiently in a worker thread.	2023-06-01 12:06:48 -04:00
sites	(core) Moving widget tests to core	2022-09-06 17:17:14 +02:00
uploads	(core) Set DateTime timezone during xlsx import	2023-05-24 11:39:49 -04:00