MegaZone wrote: > The 1xx Series2 boxes were USB1.1 hardware. All subsequent boxes have > been USB2.0 hardware, and the drivers have supported USB2.0 speeds > since 7.1 or so. (Before that they all ran at 1.1 speeds.) > > But in normal operation that really isn't the bottleneck. Transfers > on the 1xx boxes can be faster than on the 5xx boxes, because the CPU > on the 5xx maxes out first. > I dunno...I've seen some transfer speeds from, say, an R10 that a TCD1xxxxx isn't going to do. But it depends on what you're doing to maximize performance. > The first S2 units were 1xx. Then came the 2xx boxes - which include > TiVo branded units, Pioneer units, and the Toshiba SD-H400. > > The 5xx units are the 'nightlight' TiVo units (white front), all Humax > boxes, and the Toshiba RS-TX20 and RS-TX60. > > On the DirecTV side I know the R10 is based on the 5xx platform, but > I'm not sure of the mix of the earlier models - I think most of those > are based on the 2xx platform. > Correct. > Note that the Pioneer recorders are 2xx and not 5xx as you claimed > above. Only the Humax and Toshiba recorders are 5xx - they came out a > year after the Pioneer units. I have a Pioneer DVR-810H and a Toshiba > RS-TX20 and the Pioneer is definitely faster. > My bad -- I'm more of a D* guy so I always mix up the DVD units. > Huh, this is the first time I can recall hearing that there is a GigE > hack for the TiVo. So this enables support for GigE USB adapters? > Obviously the TiVo CPU is going to limit performance, since it can't > even saturate 100baseT. How much performance benefit do you really > see with the jumbo frames? > A lot, actually. In many network scenarios, the limiting factor isn't bits per second but packets per second (e.g. Cisco routers). This applies here as well. There's a whole soapbox derby thread over at DDB that gets into specifics (and more objective testing using netperf), but what I've seen with my own eyes:
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. --chris
