Scott Carey <scott@xxxxxxxxxxxxxxxxx> writes: > On 7/30/09 2:53 PM, "Tom Lane" <tgl@xxxxxxxxxxxxx> wrote: >> Scott Carey <scott@xxxxxxxxxxxxxxxxx> writes: >>> Gzip does have some quirky performance behavior depending on the chunk size >>> of data you stream into it. >> >> Can you enlarge on that comment? I'm not sure that pg_dump is aware >> that there's anything to worry about there. > For whatever reason, some other internals of gzip tend to perform much > better if submitting say, 4k or 8k or 16k chunks rather than little bits at > a time. But I'm sure some of that also depends on what library you're using > since they all vary somewhat. AFAIK there is only one widely-used implementation of zlib, and it hasn't changed much in a long time. I did some tracing and verified that pg_dump passes data to deflate() one table row at a time. I'm not sure about the performance implications of that, but it does seem like it might be something to look into. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
