Calendar-query takes long to process

[luhuec]

Hi,

I have a radicale calendar with around 1.500 events. The following request is an example where I try to receive all events from November 2025:

<?xml version="1.0" encoding="utf-8" standalone="no"?>
<C:calendar-query xmlns:C="urn:ietf:params:xml:ns:caldav">
  <D:prop xmlns:D="DAV:">
    <D:getetag/>
    <D:allprop/>
    <C:calendar-data>
      <C:comp name="VCALENDAR"/>
      <C:expand end="20251130T235959Z" start="20251101T000000Z"/>
    </C:calendar-data>
  </D:prop>
  <C:filter>
    <C:comp-filter name="VCALENDAR">
      <C:comp-filter name="VEVENT">
        <C:time-range end="20251130T235959Z" start="20251101T000000Z"/>
      </C:comp-filter>
    </C:comp-filter>
  </C:filter>
</C:calendar-query>

The request takes over 50 seconds to finish. I see a lot of these logs in the radicale log files:

...
[2025-11-18 11:29:13 +0000] [1/Thread-6934 (process_request_thread)] [INFO] Expanding event 807a24bf-c87c-44e1-9157-486fbddda55a.ics
[2025-11-18 11:29:13 +0000] [1/Thread-6934 (process_request_thread)] [INFO] Expanding event fbb62d0d-a596-4472-b34e-4f446e35ce7d.ics
[2025-11-18 11:29:13 +0000] [1/Thread-6934 (process_request_thread)] [INFO] Expanding event 80b82cc7-a79b-42f4-a526-825b209af1ef.ics
[2025-11-18 11:29:13 +0000] [1/Thread-6934 (process_request_thread)] [INFO] Expanding event 83c5c9c8-cea3-40e9-b7b5-a7932f040bd5.ics
...

Since radicale stores events in a single file per event, it looks to me that radicale takes a lot of time to open all ~1.500 files to check the date range.

Is there a way to make the processing of such a query faster?

[pbiering]

Check here (updated today): https://github.com/Kozea/Radicale/wiki/Performance-Tuning

You can try to configure dedicated location for the caching file structure and use shared memory for that (will be rebuilded on system reboot).

There are plans to collect and log some profiling data, but had no time for that so far.

[pbiering]

consider also change of caching method from default SHA256 to mtime+size (if your file system supports this proper)

[pbiering]

@flesueur found another optimization, merged with #2002

Please check latest upstream.