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Comment Re:There is a cost with all that (Score 1) 51

Whilst this is currently true, the situation is improving rapidly. I've been periodically testing the OpenELEC Kodi Jarvis alpha builds on my Raspberry Pi 2.

The previous time I tested it (a month or so ago), 720p HEVC was just playable - ~100% CPU on both cores, but only dropping the occasional frame. The time before that, 720p HEVC was unwatchable. But with build #1016 (which includes FFMPEG 2.8.1) I was getting smooth playback and averaging around 60% CPU on both cores.

HEVC will obviously never have the same hardware requirements that h264 does now, but there is a lot of work currently going into reducing the requirements.

Of course, I'd much prefer that royalty-free codecs take the fore.

Comment Failure to scale worse than crashing (Score 2) 285

We had a program that was doing session matching of RTP streams (via RTCP). We had to be able to handle a potentially very high load.

Things had been going OK - development progressing, QA testing going well. And then one day our scaling tests took a nosedive. Whereas we had been handling tens of thousands of RTP sessions with decent CPU load, suddenly we were running at 100% CPU with an order of magnitude fewer sessions.

I spent over a week inspecting recent commits, profiling, etc. I could see where it was happening in a general sense, but couldn't pin down the precise cause. And then a comment by one of the other developers connected up with everything I'd been looking at.

Turns out that we had been using a single instance of an object to handle all sessions going through a particular server, but that resulted in incorrect matching - it was missing a vital identifier. So an additional field had been added to hold the conversation ID, and an instance was created for each conversation.

Now, that in itself wasn't an issue - but the objects were stored in a hash table. Objects for the same server but different conversations compared non-equal ... but the conversation ID hadn't been included as part of the hashcode calculation. So all conversation objects for a particular server would hash the same (but compare different).

We had 3 servers and tens of thousands of conversations between endpoints. Instead of the respective server objects being approximately evenly spread across the hash map, they were all stuck into a single bucket per server ... so instead of a nice amortised O(1) lookup, we instead effectively had an O(N) lookup for these objects - and they were being looked up a lot.

The effect was completely invisible under low load and in unit tests. The hash codes weren't verified as being different in the unit tests as there was the theoretical possibility that the hashcodes being verified as different could end up the same with a new version of the compiler/library/etc.

Comment Re:VPN (Score 1) 45

What I'm getting is actually irrelevant to how Turnbull has acted, but for full disclosure, I was due to have had FTTP build in progress by now. I'm currently slated to have FTTN build started sometime in the 12 months. And I will be paying the money to apply for FoD and we'll see just how eager they are to follow up with that ...

If I had been in a fixed wireless area I'd have been pretty happy - I probably would have had it by now, and could have been on the 50/20 trial (my ISP is part of the trial).

Comment Re:VPN (Score 1) 45

Nothing Malcolm Turnbull says should be believed. There have been calls by this same government that using a VPN should be illegal, and it wouldn't surprise me in the slightest if they tried to get legislation to that effect passed.

Go read up on exactly what Turnbull (and the current government) promised about the NBN prior to the last election and everything that has gone on since.

Not only has he broken every promise or implied promise that he made before the election, but he's then gone on to make further promises that he's continued to break. Is a country using FTTN? Point at them as a shining example. Does that same country then switch away from FTTN? Either misrepresent what they're doing, or never mention them again!

The man is a consumate politician - never answers a question; immediately attacks all critics; and both claims credit for everything the previous government did (or set up and couldn't be stopped) and blames them for all the failings of the current government in the same breath. And somehow manages to keep a lot of people believing that he actually knows what he's talking about and should be believed.

The only thing he's kept to has been Tony Abbot's directive to "destroy the NBN".

Comment Re:That was the polite version (Score 1) 97

That would be "Golden Arse".

If blood were taken that way, I think you'd probably get a very different type of person doing it. SLAP, SLAP, SLAP - nope, the vein still hasn't risen up, time to get the paddles ;)

On a serious note, many thanks to James and the researchers who discovered this. Wasn't an issue for my family (Dad O-, mum O+, and my sister is O+ so OK for her too) but a literal lifesaver for many other families.

Comment Re:I'm not an encryption expert by any means... (Score 2) 220

If you know the password, your (human) perception would be that it takes slightly longer to open. The actual processing time required though would be significantly greater.

If you don't know the password, it takes that extra processing time *for each password you try* i.e. it's multiplicative. So if you're trying 300 passwords, for the part which takes 300x as long per password, it's now 90000x as long (for that part) to go through the full list.

Mommy, what happens to your files when you die?