Hi there, using 4.4 stable. I've found (I think) a weird behaviour on combining nc and tar in a pipeline through lo0 interface that causes very slow speeds when sending .tar.gz and some .pdf files.
Warning: this issue it's not really important and only happends under very specific circunstances and don't have any relevant use under productive environments, this behaviour was found coding some scripts and using lo0 interface to test them. How to reproduce it (under any version of OpenBSD): - download (for example) the sys.tar.gz file from a mirror. - do from a console with root privileges: # cd /tmp # nc -l 222 | tar xvf - - do from the dir with the sys.tar.gz file # tar cvf - sys.tar.gz | nc 127.0.0.1 222 At this point what's happening it's a pipeline with nc listening on port 222 and "untaring" what it recieves. At the other side, nc it's sending a tar file wich contains the file sys.tar.gz (that's why I mentioned this doesn't make sense and don't have any productive use, cause sys.tar.gz it's already tared and gziped) all this stuff thought lo0 interface. The issue here it's what the speed through lo0 interface when sending tar.gz files it's very slow, I experienced a 150 KB/s rate, when the normal thing it's about 10 MB/s or more. Some aclarations: - If you change the receving line for: # nc -l 222 > file.tar this issue doesn't happends, and you get the right speed (10 MB/s or more) - This only happends with the specifically combination of the "tar x" at the recieving end and the sending files contain tar.gz files (also happends with some pdf files but don't know why). - This only happends if it's through the lo0 interface. I don't have skills to determine the cause, I just thought this isn't normal, but as said, it's a really weird issue and not really productive. I didn't included dmesg cause it happends on various machines regardless the OpenBSD version. should write a sendbug?? Thanks for all! -Jesus
