Once upon a time Christopher D. Heer shaped the electrons to say... > S2 DirecTivo, 6.2, stock: ~1.8 megabytes/sec extraction > S2 DirecTivo, 6.2, backported 2.4.27 drivers: ~2.2 megabytes/sec extraction > S2 DirecTivo, 6.2, backported drivers, both tuners set to non-existent > channels: ~2.8-3.0 megabytes/sec extraction > S2 DirecTivo, 6.2, backports, non-existent channels, tweaked kernel > w/netfilter removed: ~3.4-4.0 megabytes/sec extraction > S2 DirecTivo, 6.2, backports, non-exist chans, tweaked kernel, GigE > w/jumbo frames: ~6.0 megabytes/sec extraction > > YM, as always, MV. Note that the backports aren't as critical for speed > as they used to be, since more recent Tivo sw releases (6.x/7.x/8.x) > actually include USB 2.0 drivers now. (Stock extraction from 3.1.1e > used to be around 700 kilobytes/sec.) However, they may be needed to > add support for adapters that Tivo doesn't include as stock, including > the gig adapters.
Yeah, 7.1 was the first USB2.0 release, IIRC. Certainly not-pre 7.x on standalone units. 6.x is the corresponding level for DirecTV. Anything before that would be USB1.1 drivers, so it would limit transfers quite a bit. You can see how much tuning a non-existent channel can help. .6-.8MBps. so 4.8-6.4Mbps. That's noticable over the duration of a transfer. Interesting about turning off netfilter. I wonder why that is active to start with, the TiVo isn't designed to sit on an open network, and they only listen on specific ports. I wouldn't think they need to do packet filtering or NAPT, etc, and since it seems to have a noticable performance impact, why have it in the kernel? I wonder if they're actually using it for something... I am surprised by the gains just from using jumbo frames. That is fairly significant. While it is nice to see that performance can be significantly boosted, it does make me wonder why TiVo hasn't used any of these tactics in the standard release. -MZ -- <URL:mailto:megazoneatmegazone.org> Gweep, Discordian, Author, Engineer, me. "A little nonsense now and then, is relished by the wisest men" 508-852-2171 <URL:http://www.megazone.org/> <URL:http://www.eyrie-productions.com/> Eris
