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Misc Async Writer Info (chart)

I see a chart labeled Misc Async Writer Info in the ProTop Portal. What's it about?

Before Image Writer (BIW), After Image Writer (AIW), and APW (Asynchronous Page Writer) scan activity.

Empty waits = waits for an empty BI or AI buffer to be made available.

Busy waits = waits because a BI or AI buffer was busy.

Buf flushed @ chkpt = the number of buffers not written by the APW in time and thus had to be flushed to complete a checkpoint.

APW Buf scan = the rate at which –B buffers are being scanned to find modified blocks ready to be written to disk (per second).