Huh. Maybe we turned that off? We did sit down and do some tests for the speed/size tradeoffs of using compression.
The call was just adding the compressed option to erlang:term_to_binary/2 before writing that to disk. I'm not seeing it either though. I reckon we just decided to go with no compression for speed. Paul Davis On Tue, Jan 26, 2010 at 9:55 AM, Filipe David Manana <[email protected]> wrote: > Paul, > > I don't see anything on couch_file that does compression (looking at trunk). > I grepped all the couch .erl files for "gzip" and "zlib", and the only ones > who are using compression are from the replication feature. > $ egrep -nr 'gzip|zlib' *.erl > couch_rep_att.erl:66: if ContentEncoding =:= "gzip" -> > couch_rep_att.erl:67: zlib:gunzip(Data); > couch_rep_changes_feed.erl:64: headers = Source#http_db.headers -- > [{"Accept-Encoding", "gzip"}] > couch_rep_httpc.erl:202: "gzip" -> > couch_rep_httpc.erl:203: zlib:gunzip(Body); > > Doing a quick eye scan on couch_file, I don't find anything also. > Am I missing something? > On Tue, Jan 26, 2010 at 3:24 PM, Paul Davis <[email protected]> > wrote: >> >> > I do have the same opinion as you, the code would affect many of the >> > parts >> > regarding the compression (specially couch_stream). For doc compression, >> > I >> > imagine it would touch more places, and also present some difficulties >> > to >> > assure compatibility with the previous DB file formats. >> >> Just a note that docs are already stored compressed on disk. >> Everything written through couch_file.erl gets a gzip compression >> level 6 applied if memory serves. Which suddenly makes me wonder if an >> optimization for attachment compression might benefit from turning >> that off during stream writes since the stream is already compressed. >> >> Just a couple random thoughts. >> >> Paul > > > > -- > Filipe David Manana, > [email protected] > PGP key - http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xC569452B > > "Reasonable men adapt themselves to the world. > Unreasonable men adapt the world to themselves. > That's why all progress depends on unreasonable men." > >
