[COUCHDB-761] Timeouts in couch_log are masked, crashes callers

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 0.10.1, 0.10.2, 0.11
• Fix Version/s: 0.11.1, 1.0, 1.0.3
• Component/s: Database Core
• Assignee: Unassigned
• Reporter: Randall Leeds
• Created: 13/May/10 23:01
• Updated: 07/Apr/12 22:12
• Resolved: 15/Jun/10 01:43

Description

Several users have reported seeing crash reports stemming from a function_clause match on handle_info in various gen_servers. The offending message looks like

{#Ref<>, <integer>}

.

After months of banter and sleuthing, I determined that the likely cause was a late reply to a gen_server:call that timed out, with the #Ref being the tag on the response. After it came up again today in IRC, kocolosk quickly discovered that the problem appears to be in couch_log.erl.

The logging macros (?LOG_) call couch_log/_on which calls get_level_integer/0. When this call times out the timeout is eaten and a late reply arrives to the calling process later, triggering the crash.

Suggestions on how to fix this welcome. Ideas so far are async logging or infinite timeout.