However, I don't think it is a system block because I was able to put 4 blast queries into a loop in the bash shell and fork them, and top showed all four running at the same time.

That really doesn't make any sense at all.

When you spawn blast from several threads, the blast instances are running as separate processes, so should be completely unaffected by anything in the parent process, regardless of whether it is using threads or not.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

In reply to Re^4: Multithreads with an executable in the worker subroutine by BrowserUk
in thread Multithreads with an executable in the worker subroutine by lskatz

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