Enabling System Caching

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jjsyht
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Enabling System Caching

Post by jjsyht »

Hi,

I have multiple jobs referencing the same hash file. I'm guessing I should use System caching for faster speed. Many of these jobs run at the same time

I could not see (from HashFile Disk Caching Tech. Bulletin) how to specify that a hash should be in the system cache.

There's something about "CATALOG.FILE.CACHE <filename>". If this is what I have to do, where do I do that?
ray.wurlod
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Post by ray.wurlod »

Welcome aboard.

There's rather more to it than that, as a more detailed reading of that manual will reveal. You are correct about CATALOG.FILE.CACHE but, before that, the hashed file itself must be made capable of being a public cached hashed file. Review the manual, then come back if you have further questions.
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jjsyht
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Post by jjsyht »

Thanks, this board has been very helpful.

It's good to know I'm on the right track.
The parameters for using Private/Public link caching is pretty straightforward in the manual, however using the System cache seem to be some level above the other two.

I'm thinking that the parameters for System Cache should be the same as Public Cache +
1. Set caching attribute as Write Deferred/Immediate.
2. Put the file in the CATALOG.

However we have 2 seperate stages. First is to write the hash files, and only then do we reference it. So therefore the (write) caching attribute seem of no use. I suppose it's no harm having the parameter as Write deferred.
I'll experiment.

Again, thanks
jjsyht
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Post by jjsyht »

System Caching in use... READ-ONLY file cache enabled, overriding link private cache

What has been said above is everything that needs to be done.
And (write) caching shouldn't be set to "None"... no matter if it doesn't seem necessary.

Off to the more boring task of modifying all the jobs now.
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