On 28/06/2013 9:56 PM, Hunkeler, Peter (TLSG 4) wrote:
The application is opening a large number of input files with the C/C++
fopen convention as fopen("//DD:INPUT(member)","r") .
Is this read only data? if so, would it be an option to copy the PDS members
into a TFS file system (one of your own), say after an IPL and leave them there
for your application? TFS access is memory only and should be fast.
I agree with Peter. If the files are transient TFS is the way to go.
Even if they were persistent the z/OS unix file system may be a good
choice.
Reads are fast (ZFS has a LRU file cache). Writes are also speedy. My
simple benchmarks on a z114 with a fibre attached IBM SAN showed that ZFS
significantly outperformed the likes of QSAM by a significant amount.
I just think about convert the original input PDS(E) file into a memory
files according this syntax.
You mean naming the files //DD:INPUT(member)? The //DD: is triggering
MVS OPEN in C/C++ instead of file system open. I suspect this will not work.
--
Peter Hunkeler
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