Re: Determine number of dirty blocks...

There is some ambiguity in your question.

When I make a change to a block, it is a "dirty block" in that the image in memory does not match the image on disc.

If the block is written from the buffer to disc before I commit the change, then the block is a "dirty block" that will be subject to future 'delayed block cleanout' and does not immediately reflect the true state of the date.

If the block is in memory when I commit, the block may be partly modified to reflect the commit, but will still be a "dirty block" in that the lock bytes will still be marking the rows I have changed as locked, and a subsequent modification of the block will do a 'delayed logging' clean out.

Of the three variations, the second is perhaps the only one that might be significant, as any attempt to read the block will result in it being modified in memory (and therefore becoming "dirty" in the first sense) resulting in the generation of redo log and a future write.

Any attempt to count such blocks will only clean them.

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Clayton Hinkle wrote in message ...


>Anyone know of a way to determine how many dirty blocks you have in

>the database at any given time?

>

>Thanks!

>

>--Clayton