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Topic: NXT :: descendant of Bitcoin - Updated Information - page 872. (Read 2761624 times)

sr. member
Activity: 338
Merit: 250
Running 0.7.5:

I get a non-stop list of this:

height 66516 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:24.534] DEBUG: Failed to accept block 11979910396361888590 at
height 66516 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:26.139] DEBUG: Failed to accept block 11979910396361888590 at
height 66516 received from node3.mynxtcoin.org, blacklisting
[2014-02-14 22:01:27.190] DEBUG: Failed to accept block 11979910396361888590 at
height 66516 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:28.239] DEBUG: Failed to accept block 11979910396361888590 at
height 66516 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:40.314] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from node3.mynxtcoin.org, blacklisting
[2014-02-14 22:01:41.923] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from node3.mynxtcoin.org, blacklisting
[2014-02-14 22:01:42.979] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:44.029] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:45.634] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from node3.mynxtcoin.org, blacklisting
[2014-02-14 22:01:46.697] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:47.748] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:48.810] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:50.821] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from node3.mynxtcoin.org, blacklisting
[2014-02-14 22:01:51.923] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from vps2.nxtcrypto.org, blacklisting
[2014-02-14 22:01:53.745] DEBUG: Failed to accept block 12715248329747037589 at
height 66517 received from node90.nxtbase.com, blacklisting


EDIT: okay, seems to have stopped now after several hundred lines of this.
sr. member
Activity: 392
Merit: 250
Interesting. Why can't this be undone?
Because to find out the previous value of the alias URL, if any, you need to go back through all previous transactions. In effect, again scanning the blockchain.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
du says: 257480 for current nxt_db folder
What? Mine is 111M only.

Err:
Code:
pi@raspberrypi ~/nxt $ du -h nxt_db/
252M nxt_db/

Wrong usage of du?
sr. member
Activity: 392
Merit: 250
Does this mean that we are actually generating checkpoint files on all the nodes all the time? If so, how much work would it be to have newly installed nodes query for the most recent db files and start with that, instead of redownloading the entire blockchain. Of course, must be peer verified checksums, etc.
I don't understand what you mean by checkpoint file. The rest is a bad idea.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Alias assignment being undone? I didn´t touch the client when this message came.
It is not because of something you did. The block that had to be popped off contained an alias assignment transaction. When a block is popped off, an attempt is made to undo all transactions in it. But this type of transaction cannot be undone, and in this case a full rescan of the blockchain is needed.

Interesting. Why can't this be undone?
sr. member
Activity: 392
Merit: 250
du says: 257480 for current nxt_db folder
What? Mine is 111M only.
sr. member
Activity: 392
Merit: 250
Alias assignment being undone? I didn´t touch the client when this message came.
It is not because of something you did. The block that had to be popped off contained an alias assignment transaction. When a block is popped off, an attempt is made to undo all transactions in it. But this type of transaction cannot be undone, and in this case a full rescan of the blockchain is needed.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?
Does this mean that we are actually generating checkpoint files on all the nodes all the time? If so, how much work would it be to have newly installed nodes query for the most recent db files and start with that, instead of redownloading the entire blockchain. Of course, must be peer verified checksums, etc.

How fast does the DB grow at 1000TPS?



du says: 257480 for current nxt_db folder
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Not, if the runtime for calculating a sig is dependent on the number of bits of the payload.

It is a common misconception that basic operations are in O(1), but that's wrong. Even addition and multiplication of larger numbers take longer than of smaller numbers. The same hodls for sig function.

I like the conceptual idea of having set-based transactions because set-based thinking is one of the principle of modern computer science.

What I was trying to explain to you was that you should not make not unproven statements.
Show me the runtime complexity of the sig function in terms of payload length and we'll see.

NRS signs SHA256 of a message.

1 signature takes 100 times more CPU ticks than SHA256(32_random_bytes). Signing of a transaction that is 100 times longer ~ 2 ordinary signatures.

Not sure, I got it.

The runtime complexity is still O(n)? But the factory in between is 100? (n = number of bits)

Complexity of signing is O(1).

That is plain wrong. The more bits you have to sign the longer signing takes. The question is: how long in terms of the input length.
legendary
Activity: 1176
Merit: 1134
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?
Does this mean that we are actually generating checkpoint files on all the nodes all the time? If so, how much work would it be to have newly installed nodes query for the most recent db files and start with that, instead of redownloading the entire blockchain. Of course, must be peer verified checksums, etc.

How fast does the DB grow at 1000TPS?

legendary
Activity: 2142
Merit: 1010
Newbie
Not, if the runtime for calculating a sig is dependent on the number of bits of the payload.

It is a common misconception that basic operations are in O(1), but that's wrong. Even addition and multiplication of larger numbers take longer than of smaller numbers. The same hodls for sig function.

I like the conceptual idea of having set-based transactions because set-based thinking is one of the principle of modern computer science.

What I was trying to explain to you was that you should not make not unproven statements.
Show me the runtime complexity of the sig function in terms of payload length and we'll see.

NRS signs SHA256 of a message.

1 signature takes 100 times more CPU ticks than SHA256(32_random_bytes). Signing of a transaction that is 100 times longer ~ 2 ordinary signatures.

Not sure, I got it.

The runtime complexity is still O(n)? But the factory in between is 100? (n = number of bits)

Complexity of signing is O(1).
hero member
Activity: 784
Merit: 500
What does this mean?


[2014-02-14 10:39:40.346] DEBUG: Will pop block 5073332198957728923 at height 66148
[2014-02-14 10:39:40.347] DEBUG: Will pop block 8348856438008341233 at height 66147
[2014-02-14 10:39:40.348] DEBUG: Reversal of alias assignment not supported
[2014-02-14 10:39:40.348] DEBUG: Popping off last block not possible, will do a rescan
[2014-02-14 10:39:40.349] Re-scanning blockchain...
[2014-02-14 10:39:54.734] ...Done
[2014-02-14 10:39:54.737] DEBUG: Generate block failed: Previous block id doesn't match

This is all normal, works as intended. It is telling you exactly what is happening - popping off a block, doing a rescan because alias assignment cannot be simply undone in a pop-off. The block generation attempt failed because in the meantime another block arrived and was accepted.


Alias assignment being undone? I didn´t touch the client when this message came.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
when you update, you just dump the old nxt_db directory into the nxt_db in the unzip directory of the new version, and the blockchain won't be downloaded -just as with before, when you could just dump the blocks.nrs and transactions.nrs into the new version.
only then it would crash very often, and now with sql it hopefully won't.

At least that's what I understand from it.


Well, I see. I don't think we were talking about the 'manual performance of upgrading' but the runtime performance, though.

But, you are right. That's the idea of having a database which is able to handle transactions, rollbacks, caching, indexing etc. at once. Much better than inventing your own serialization format. +1
legendary
Activity: 1181
Merit: 1018
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?

What exactly do you mean by performance?

1) startup is slow as always. Especially these migrations

2) running is as good as always. Does not go above 5%.

3) RAM consumption is 1% lower.

yes, which is why having the option of using the nxt_db is quite helpful


Why is that? Or maybe, I didn't understand what you mean.

when you update, you just dump the old nxt_db directory into the nxt_db in the unzip directory of the new version, and the blockchain won't be downloaded -just as with before, when you could just dump the blocks.nrs and transactions.nrs into the new version.
only then it would crash very often, and now with sql it hopefully won't.

At least that's what I understand from it.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?

What exactly do you mean by performance?

1) startup is slow as always. Especially these migrations

2) running is as good as always. Does not go above 5%.

3) RAM consumption is 1% lower. Still 87% of total memory.

yes, which is why having the option of using the nxt_db is quite helpful


Why is that? Or maybe, I didn't understand what you mean.
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Not, if the runtime for calculating a sig is dependent on the number of bits of the payload.

It is a common misconception that basic operations are in O(1), but that's wrong. Even addition and multiplication of larger numbers take longer than of smaller numbers. The same hodls for sig function.

I like the conceptual idea of having set-based transactions because set-based thinking is one of the principle of modern computer science.

What I was trying to explain to you was that you should not make not unproven statements.
Show me the runtime complexity of the sig function in terms of payload length and we'll see.

NRS signs SHA256 of a message.

1 signature takes 100 times more CPU ticks than SHA256(32_random_bytes). Signing of a transaction that is 100 times longer ~ 2 ordinary signatures.

Not sure, I got it.

The runtime complexity is still O(n)? But the factory in between is 100? (n = number of bits)
legendary
Activity: 1181
Merit: 1018
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?

What exactly do you mean by performance?

1) startup is slow as always. Especially these migrations

2) running is as good as always. Does not go above 5%.

3) RAM consumption is 1% lower.

yes, which is why having the option of using the nxt_db is quite helpful
sr. member
Activity: 364
Merit: 250
☕ NXT-4BTE-8Y4K-CDS2-6TB82
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?

What exactly do you mean by performance?

1) startup is slow as always. Especially these migrations

2) running is as good as always. Does not go above 5%.

3) RAM consumption is 1% lower. Still 87% of total memory.
legendary
Activity: 1181
Merit: 1018
Question: Is it possible to re-use the nxt_db directory when upgrading from 0.7.4 to 0.7.5  without downloading the whole blockchain again?
Yes, it is designed to be possible to upgrade without having to delete the nxt_db directory, that's the reason I bother with applying those SQL statements.

If too slow for Raspberries, do whichever is faster, upgrade or download from scratch.

Did I manage to improve the Raspberry performance with the last release?

once the blockchain is complete 0.7.4 is running quite smoothly at 1-3% cpu, and given lots of ram:

top
                                                              
 2040 pi        26   6  993m 385m 2768 S   1,0 88,0  61:54.85 java                                                                      
 3318 pi        20   0  4880 1324  976 R   1,0  0,3   0:01.18 top        

I think also the blockchain download was faster with 0.7.4, but I can't really tell, because I did not monitor the dl all the time ...
legendary
Activity: 1181
Merit: 1018
Thanks! I am reluctant about the overclocking, but I run it with -856xmx ...

What does -856xmx do?

It is the memory available to the jvm, I quoted it wrong:

ps -ax
 2040 ?        SNl   61:45 /usr/bin/java -Xms128m -Xmx856m -jar start.jar STOP.PORT=7873 STOP.KEY=0815


-Xms128m is the minimum that is reserved at the start, and -Xmx856m is the maximum it can have, in megabytes. I often had crashes with a maximum smaller 450MB, but with giving it almost all the memory, it runs quite good.

Except that dl'ing the whole blockcahin is quite some venture.
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