[BUG] Severe performance regression since 1.17.9

[eugenesan]

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Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

Session "grabs" 2 CPU cores at 35-50% on start and never releases.
One of the processes is renderer and the other is not.

Expected Behavior

Session shouldn't cause high CPU usage constantly

Steps To Reproduce

1. Start session v1.17.9 or v1.17.10
2. Obverse high CPU usage.
3. Downgrade to 1.17.8 and observe regular CPU usage

Desktop Version

1.17.10

Anything else?

Linux 6.17 on Intel i7-6500
Session AppImage on Ubuntu 25.10
1.17.19 and 1.17.10 are affected
1.17.8 works just fine

Here are a few difference in the log:

{"level":30,"time":"","msg":"starting session-desktop version 1.17.8"}
{"level":30,"time":"","msg":"Libsession Commit Hash: libsession-util v1.5.8-nogit"}
{"level":30,"time":"","msg":"Libsession NodeJS Version/Hash: 0.6.9/unknown"}

vs

{"level":30,"time":"","msg":"starting session-desktop version 1.17.9"}
{"level":30,"time":"","msg":"Libsession Commit Hash: libsession-util v1.5.9-nogit"}
{"level":30,"time":"","msg":"Libsession NodeJS Version/Hash: 0.6.10/unknown"}

---

{"level":30,"time":"","msg":"updateSessionSchema: Current loki schema version: 53; Most recent schema version: 52;"}

vs

{"level":30,"time":"","msg":"updateSessionSchema: Current loki schema version: 53; Most recent schema version: 53;"}

---

{"level":30,"time":"","msg":"messages count 434"}
{"level":30,"time":"","msg":"messages_fts count 434"}
{"level":30,"time":"","msg":"messages_fts_config count 1"}
{"level":50,"time":"","msg":"{\"code\":\"SQLITE_ERROR\"}"}
{"level":30,"time":"","msg":"messages_fts_content count 0"}
{"level":30,"time":"","msg":"messages_fts_data count 26"}
{"level":30,"time":"","msg":"messages_fts_docsize count 449"}
{"level":30,"time":"","msg":"messages_fts_idx count 24"}

vs

{"level":30,"time":"","msg":"messages entries count: 434"}
{"level":30,"time":"","msg":"messages_fts_config entries count: 1"}
{"level":30,"time":"","msg":"messages_fts_data entries count: 26"}
{"level":30,"time":"","msg":"messages_fts_docsize entries count: 449"}
{"level":30,"time":"","msg":"messages_fts_idx entries count: 24"}

The issue is persistently reproducible when going back and forth with the same config folder.