Insert into getCopyDataMessage() the same logic that already existed in the
main code path for enlarging libpq's input buffer in one swoop when needing to read a long data message. Without this, the code will double the buffer size, read more data, notice it still hasn't got the whole message, and repeat till it finally has a large enough buffer. Which wastes a lot of data-moving effort and also memory (since malloc probably can't do anything very useful with the freed-up smaller buffers). Not sure why this wasn't there already; certainly the COPY data path is a place where we're quite likely to see long data messages. I'm not backpatching though, since this is just a marginal performance issue rather than a real bug.
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $PostgreSQL: pgsql/src/interfaces/libpq/fe-protocol3.c,v 1.33 2008/01/15 22:18:20 tgl Exp $
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* $PostgreSQL: pgsql/src/interfaces/libpq/fe-protocol3.c,v 1.34 2008/01/17 21:21:50 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -1305,7 +1305,24 @@ getCopyDataMessage(PGconn *conn)
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}
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avail = conn->inEnd - conn->inCursor;
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if (avail < msgLength - 4)
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{
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/*
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* Before returning, enlarge the input buffer if needed to hold
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* the whole message. See notes in parseInput.
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*/
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if (pqCheckInBufferSpace(conn->inCursor + msgLength - 4, conn))
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{
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/*
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* XXX add some better recovery code... plan is to skip over
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* the message using its length, then report an error. For the
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* moment, just treat this like loss of sync (which indeed it
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* might be!)
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*/
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handleSyncLoss(conn, id, msgLength);
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return -2;
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}
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return 0;
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}
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/*
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* If it's a legitimate async message type, process it. (NOTIFY
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