Saturday, 28 July 2012

Day 4 - Now we hit the big time

Today is the first time that my recording system will be truly stress tested, with a packed schedule of 51 recordings across all 24 satellite channels (plus all the terrestrial recordings on top of that). This means it marks the debut of BBC Olympics HD channels 4-24 in showing actual live Olympics sport (rather than timetable video or the torch relay).

My quad sat tuner cards are actually two twin tuners on one circuit board, so with tuner 4 on one card out of action, it was predictable that another tuner would fail shortly after and that's what happened this morning (tuner 2 on pc1 - I guess they alternate on the connectors?). The good news is that I mis-typed one of the transponder numbers in the program I finished yesterday, so it does look like you can just about scrape by on 6 tuners today with absolutely no overlap though.

What I've done is allocate all sports strings to Automatic Recording on both PCs and then manually abort events which one of the two PCs can't find a tuner to record on. I can now see five 8+ hour tennis sessions today starting at 11:30 or 12:00, so that's going to be "fun". So far, I've managed to record everything, but it's probably my first all-day "dressing gown" session of the Olympics :-)

As I suspected, it got very tight at lunchtime on pc2's SSD since that's the more heavily loaded of the two. I ended up stopping and deleting the terrestrial recordings on pc2 because I'm doubling up on all of those. The problem is that the BBC haven't split up long slots into sub-events (tennis being the worst - 5 slots of over 8 hours each) so many of them start in the morning and either break at lunch or go on right through lunch continuously, so 4-6 hour single slots are quite common.

This means my SSD->HDD copier has more simultaneous long slots to deal with and hence a lot more SSD space is needed. As a precaution, I've now turned off all terrestrial recordings on pc2 and will just record them on pc1 only from now on. Things have calmed down since I've done that, with pc2 SSD usage around 50-60% now (but this will climb this afternoon of course). The only actual gap between events starting today that is longer than an hour is at 15:25-16:50, which I finally get a break (once events are recording, I can relax a bit and leave them unattended).

The latest starting time today is 20:25 (boxing), so once that's started recording, I'll get to watch the recording of today's Hungarian F1 GP qualifying which has been rudely shoved to BBC Two and in SD only :-( At least the race tomorrow is on BBC One HD - yay! - although only a 90-minute long highlights show sadly. The only other non-Olympics activity tonight is the lottery show at 10.20pm on BBC One HD, where I'll be updating my unofficial lottery site at the same time as the show airs (unlike Camelot's official site...).

Around about 15:30 today, pc2's SSD started to exceed 90%, so I found a way to free up space manually. I stopped my transmedia program temporarily so I could move stuff without a verify (and 5-10 mins earlier), then I targeted the ludicrous 8+ hour tennis slots (8 hours and 40 mins is the longest - 2 hours longer than today's road race slot!) and split them at the half-way point like the bleeding BBC should have done. I did this by stopping the recording for a few seconds and starting it again - the fresh recording uses a numerically incremented separate filename and then I could move the original (4+ hours!) recording from SSD to HDD and free up some 20-25GB of space in one go. I will probably have to do this wiith anything that exceeds a 6 hour slot in the future.

I didn't know what to do with Freeview channel 304 (an HD version of red button channel 301) when I was first setting up the terrestrial channels and I decided that because I was recording all the sports in HD already and also 301 in SD, it would be a duplicate almost all the time. However, now I'm down to recording everything just once, I've activated the recording of 304 as a precaution on pc1 (which is fine with its SSD free space at peak times).

I guess hindsight is a wonderful thing - if I'd have known about all these problems in advance, I'd have got dishes with octo LNBs instead of quad LNBs, four quad tuner sat cards instead of two and 480GB SSDs instead of 240GB. That way, any two tuner failures wouldn't have mattered and I wouldn't nearly have run out of SSD space either. Plus I'd have been able to record everything twice, which would have been a bonus and would allow me to leave the whole setup mostly unattended.

I made the mistake of believing the blurb for the sat cards when they said they could record 48 HD channels simultaneously. The problem with the Astra satellites is that their transponder bandwidth is around 45Mbit/s and the BBC uses around 10-11 Mbit/sec for their HD channels, so there was never going to be enough tuners (4 tuners * 4 HD channels = 16) with a single quad card to cover the 24 channels. The cards took weeks to arrive and I finished my sat installation a few months ago, so I'd already lost some redundancy before the 2 tuners gave up on me. If it was as easy as just ordering two more cards, I'd have done it, but it would also require a quad LNB -> octo LNB replacement and another four cables off of each dish, which is yet another callout for a sat installer.

My Automatic Recording strings picked up Now/Next info for unscheduled fourth and fifth 8+ hour tennis slots (11:30-20:00) on channels 23 and 24, which I recorded (with mid-slot splits like I mentioned earlier). I say "unscheduled" because digiguide.tv's site that I paid a subscripion for failed to list anything on channels 23 and 24 today :-( It definitely pays to use the Now/Next (EIT) system I guess!

I actually went to bed early tonight (yes, before the last events had finished recording!) because I was so tired monitoring the recordings. The problem is that tomorrow is even busier, but now I know what to do with the long slot events, things should be a lot less frantic (i.e. not 90%+ full on pc2's SSD). Apart from serial offenders equestrianism (7 hours) and tennis (8+ hours), it looks like sailing (over 6 hours) is another sport for the split treatment for overly long slots.

Day 4 recording size: 961GB (a new record) - grand total so far: 1781GB (1.7TB)
In case you think I'll run out of space in a few days, don't worry - I have about 25TB of HDD space available for the recordings (8 * 3TB and 2 * 2TB - you never get the full 2TB/3TB remember).

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