Upload applet very slow with 9k jumbo frames
|Posted: Fri, 2008-07-25 02:04|
I'm using the latest Gallery 2.x from SVN, running on Fedora 9, and the latest revision of Sun Java (v6, update 7). This may be a java issue more than a GR issue, but the upload applet runs at about 12kB/sec. over a LAN when running 9000 byte jumbo frames. If I change the server MTU to 8231 (or lower), it works at full speed. I have no idea why 8231 is the magic number, but 8232-9000 causes the problem. I have tested this on 3 different machines having 3 different gigabit NICs and with the latest drivers.
I used to have this problem with other programs such as FlashFXP, Openwebmail, and Outlook Express (all on the upstream side), but all of those went away with changing the LAN request buffer size (http://support.microsoft.com/default.aspx?scid=kb;en-us;Q320829) and then by my transition to Vista. Adding the buffer size registry key to Vista has no effect on this issue, and all of the previously mentioned programs work fine without it.
This is more of a curiosity/annoyance than anything, but GR seems to be the only thing left that shows this behavior.