in reply to garbage collection not happening?

You need to be using Net::SFTP instead of Net::SSH::Perl. Net::SFTP has do_open(), do_read(), and do_close() methods which behave very similarly to sysopen(), sysread(), and sysclose(). Granted, you don't have the nice split-on-$/ behavior of normal filehandles, but you won't blow your memory out, either.

Of course, you could just pull the logfile into tempspace and read it there ...

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