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WSupported on Windows
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USupported on Unix
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NSupported in Synergy .NET
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The IU_FEEDERTHREADS environment variable specifies the number of feeder threads.
Value
The number of feeder threads, in the range 0 – 8. The default is the number of CPUs divided by 2.
Discussion
When isutl is run, the “main thread” passes memory-mapped records to a “feeder thread” via a lock-free queue. The feeder thread then uncompresses the records, if necessary, and extracts the keys, passing them to individual “key threads” via a set of key queues. The key threads use the data as input to the first phase of the sort, which eventually gets written out as partially sorted runs. This keeps the data in transit longer before being written out, and multiple keys can be processed simultaneously. The IU_FEEDERTHREADS environment variable enables you to change the number of feeder threads.
Setting location
The environment.
Used by
isutl utility, fconvert utility
Examples
On Unix,
IU_FEEDERTHREADS=2 ;export IU_FEEDERTHREADS
