Instead of using a ramfs to store large blocks of data, why not get rid of the external process running gzip. Instead use PerlIO::gzip and process the file line by line. According to the POD:

use PerlIO::gzip;
open FOO, "<:gzip", "file.gz" or die $!;
print while <FOO>;         # And it will be uncompressed...

binmode FOO, ":gzip(none)" # Starts reading deflate stream from here o
+n
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