RCVOPT parameter

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Recovery options


Default value
Parameter type
Where set
On User 0's parameter line
Related products
Model 204 V2.1 or earlier


Valid settings of RCVOPT are (options can be summed):

Setting Meaning
X'01' Checkpoints are taken.
X'08' Roll forward information is logged into the journal stream.
X'20' Do not flush the dirty pages in a file that does not do pre-imaging (FRCVOPT X'20' set) during a subtransaction checkpoint. This bit has an effect in Model 204 7.6 and later; for V7.5, it requires an appropriate maintenance zap.

One use of this setting is to set FRCVOPT X'20' for a file that holds SirFact dumps, which can get quite large. This bit prevents a large SirFact dump from causing a subtransaction checkpoint to take a very long time. While this might result in a SirFact dump being lost if the system crashes, such a loss is probably not that critical, so its risk is probably well worth the benefit of faster subtransaction checkpoints.