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ASF GitHub Bot commented on COUCHDB-2425: ----------------------------------------- GitHub user mikewallace1979 opened a pull request: https://github.com/apache/couchdb/pull/297 Add config variable for get_proc_timeout This commit adds the couchdb/get_proc_timeout config variable to default.ini. This is used by couch_query_servers when getting a reference to an external process. Previously this value was always infinity which meant that if anything went wrong in the gen_server call to get_proc the process would hang around indefinitely. COUCHDB-2425 You can merge this pull request into a Git repository by running: $ git pull https://github.com/mikewallace1979/couchdb-1 2425-fix-dangling-couch_query_server-procs Alternatively you can review and apply these changes as the patch at: https://github.com/apache/couchdb/pull/297.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #297 ---- commit 96db341bbf0cd0cab3a6cf035c004a3d9a503c6f Author: Mike Wallace <mikewall...@apache.org> Date: 2015-01-14T18:28:26Z Add config variable for get_proc_timeout This commit adds the couchdb/get_proc_timeout config variable to default.ini. This is used by couch_query_servers when getting a reference to an external process. Previously this value was always infinity which meant that if anything went wrong in the gen_server call to get_proc the process would hang around indefinitely. COUCHDB-2425 ---- > Exceptions in couch_proc_manager:new_proc/1 leave dangling couch_query_servers > ------------------------------------------------------------------------------ > > Key: COUCHDB-2425 > URL: https://issues.apache.org/jira/browse/COUCHDB-2425 > Project: CouchDB > Issue Type: Bug > Security Level: public(Regular issues) > Components: JavaScript View Server > Affects Versions: 2.0.0 > Reporter: Mike Wallace > Fix For: 2.0.0 > > > If an exception is thrown in the try blocks in either of the > couch_proc_manager:new_proc/1 clauses [1] [2] then a spawn_error is returned > which is handled by a specific handle_info clause [3] which does not reply to > the calling process. When the caller is couch_query_servers:get_os_process/1 > [4] there is an infinite timeout so that process will hang around until > either the node reboots or someone intervenes. > The user-facing symptom is an entry in _active_tasks that makes no progress > and never goes away. > The easiest way to reproduce this is to create a new view and then patch the > code to force an exception in the appropriate place, e.g.: (assuming a live > dev/run instance): > 1. Create DB, add a ddoc and a doc: > {code} > $ curl -X PUT http://localhost:15984/kitteh > {"ok":true} > $ curl -X POST http://localhost:15984/kitteh -d '{"_id":"_design/view", > "views": {"test": {"map": "function(doc) { emit(doc.id, 1); }"}}}' -H > 'Content-Type: application/json' > {"ok":true,"id":"_design/view","rev":"1-ef10f980522d4c8e691e3c26d4c3fac5"} > $ curl -X PUT http://localhost:15984/kitteh/ohai -d '{}' > {"ok":true,"id":"ohai","rev":"1-967a00dff5e02add41819138abb3284d"} > {code} > 2. Apply https://gist.github.com/mikewallace1979/79f823da25f6a78e2725 then > re-run make and dev/run. > 3. Attempt to query the view: > {code} > $ curl -X GET http://localhost:15984/kitteh/_design/view/_view/test > {"error":"timeout","reason":"The request could not be processed in a > reasonable amount of time."} > {code} > 4. Observe index build tasks which never go away: > {code} > $ curl -X GET http://localhost:15986/_active_tasks > [{"pid":"<0.2403.0>","changes_done":0,"database":"shards/40000000-5fffffff/kitteh.1414779043","design_document":"_design/view","progress":0,"started_on":1414779439,"total_changes":1,"type":"indexer","updated_on":1414779439},{"pid":"<0.2444.0>","changes_done":0,"database":"shards/00000000-1fffffff/kitteh.1414779043","design_document":"_design/view","progress":0,"started_on":1414779439,"total_changes":1,"type":"indexer","updated_on":1414779439}] > {code} > [1] > https://github.com/apache/couchdb-couch/blob/master/src/couch_query_servers.erl#L354 > [2] > https://github.com/apache/couchdb-couch/blob/master/src/couch_proc_manager.erl#L368-L384 > [3] > https://github.com/apache/couchdb-couch/blob/master/src/couch_proc_manager.erl#L239-L245 > [4] > https://github.com/apache/couchdb-couch/blob/master/src/couch_query_servers.erl#L354 -- This message was sent by Atlassian JIRA (v6.3.4#6332)