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Fix some leftovers from the SESSION->MXS_SESSION and related renames

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Renames only.
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Esa Korhonen
2017-01-18 10:36:18 +02:00
parent 46e9e6f4e7
commit 00f77bbe69
8 changed files with 16 additions and 16 deletions
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Documentation/Reference/How-errors-are-handled-in-MaxScale.md
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@ -38,7 +38,7 @@ When client protocol module receives query from client the protocol state is (ty
### Backend failure
When mysql_client.c:gw_read_client_event calls either route_by_statement or directly SESSION_ROUTE_QUERY script, which calls the routeQuery function of the head session’s router. routeQuery returns 1 if succeed, or 0 in case of error. Success here means that query was routed and reply will be sent to the client while error means that routing failed because of backend (server/servers/service) failure or because of side effect of backend failure.
When mysql_client.c:gw_read_client_event calls either route_by_statement or directly MXS_SESSION_ROUTE_QUERY script, which calls the routeQuery function of the head session’s router. routeQuery returns 1 if succeed, or 0 in case of error. Success here means that query was routed and reply will be sent to the client while error means that routing failed because of backend (server/servers/service) failure or because of side effect of backend failure.
In case of backend failure, error is replied to client and handleError is called to resolve backend problem. handleError is called with action ERRACT_NEW_CONNECTION which tells to error handler that it should try to find a replacement for failed backend. Handler will return true if there are enough backend servers for session’s needs. If handler returns false it means that session can’t continue processing further queries and will be closed. Client will be sent an error message and dcb_close is called for client DCB.
@ -52,5 +52,5 @@ Reasons for "backend failure" in rwsplit:
### Router error
In cases where SESSION_ROUTE_QUERY has returned successfully (=1) query may not be successfully processed in backend or even sent to it. It is possible that router fails in routing the particular query but there is no such error which would prevent session from continuing. In this case router handles error silently by creating and adding MySQL error to first available backend’s (incoming) eventqueue where it is found and sent to client (clientReply).
In cases where MXS_SESSION_ROUTE_QUERY has returned successfully (=1) query may not be successfully processed in backend or even sent to it. It is possible that router fails in routing the particular query but there is no such error which would prevent session from continuing. In this case router handles error silently by creating and adding MySQL error to first available backend’s (incoming) eventqueue where it is found and sent to client (clientReply).