synchronous CA performance (XP-512)

[Willem Polder_1]

Can I affect performance of a CA-link by using the -c option of the paircreate command over a synchronous CA-link (both ends XP-512)?
If so, is it wise to do so in a live large DB environment (4500 users/6TB database)

[Vincent Fleming · Accepted solution]

You cannot affect the performance of the link. What the Copy Pace parameter does is define the number of tracks that can be modified before Host writes are blocked. Basically, it defines how far behind your copy is. With Synchronous, it defines how many write I/Os you can have in-flight at any given time for the pair.

The XP will always use as much of the remote link as it can... as long as Host write activity is less than your pipe has bandwidth, you should be good.

Setting the Copy Pace higher will allow bursts of data to the volume to be accepted (up to 15 I/Os) without degrading performance. Lowering this value will degrade Host performance (not copy performance) if your bursts exceed the value you set.

Is it wise to tweak this value? Probably not.

Good luck,

Vince