Quote from: Mike Hearn on May 16, 2013, 04:57:05 PM

You don't send a full locator every time a new block is mined. Nodes are supposed to send a getdata and only do a getblocks if what they get back is an orphan.

Of course I don't.
But I am saying that this is what I get from a bunch of nodes running the official client, often after a new block has been mined.
I have no idea why they do it, but feel free to explain it to me..

Quote from: Zeilap on May 16, 2013, 04:57:36 PM

Quote from: piotr_n on May 16, 2013, 04:05:58 PM

Again: this wastes a hell lot of bandwidth, generating lots of traffic in the network each time a new block is mined.

No. That's not how it works.

Are you saying that I am sending all these screwed up "getblocks" to myself, from all the different IPs - or are you saying that I am lying about what I see?
Or maybe I'm just crazy and what I see is not real...

Quote

If you do this after the last checkpoint, you're in for a surprise. Good luck.

Thanks, but I don't use any checkpoints, so I don't think I'm going to need any luck here.

It's very simple:
1) measure a time difference between now and when you received your last block - divide it by whatever period you like, to get a number (I use minutes)
2) then go back the chain, starting from the head, as many blocks up, as the number from point 1 was
3) pass the hash of the block you have reached in point 2 to "getblocks" - and voila.
Using such a simple way, you can recover from basically any fork, as long as it isn't longer than a couple of hundreds blocks. And if a fork would happen o be longer, I will surely have enough time to develop an improvement before it's actually needed