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<== Date ==> | <== Thread ==> |
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Subject: | Erratum: Lock/Mutex to prevent "caget" from cutting in between updating multiple fields |
From: | Ralph Lange <[email protected]> |
To: | EPICS Tech-Talk <[email protected]> |
Date: | Mon, 2 May 2016 08:54:03 +0200 |
I got one important thing wrong. On 01/05/2016 10:57, Ralph Lange wrote:
That last statement is wrong. The reference in the queue entry is pointing to the record, not to the data. The timestamp and data parts of a single update sent to the client are always matching and consistent. However, when there are multiple updates for the same array-type value in a client's queue, the same timestamp/data (taken from the record) will be sent to the client multiple times. This can happen when an I/O Interrupt scanned waveform record gets a burst of scans. Thanks to Michael Davidsaver for pointing this out, and sorry for not doing proper fact-checking in the first place. Cheers, ~Ralph |