Tom Lane wrote:
> I would bet that the reason for the slow throughput is that gzip
> is fruitlessly searching for compressible sequences. It won't find many.
>
Indeed, I didn't expect much reduction in size, but I also didn't expect
a four-order of magnitude increase in run-time (i.e. output at
10MB/second going down to 500KB/second), particularly as my estimate was
based on gzipping a previously gzipped file. I think it's probably
pathological data, as it were. Might even be of interest to gzip's
maintainers.