Automatically adjusting Spam Block

ptschip commented at 3:56 pm on October 10, 2015: contributor

Auto adjusts -limitfreerelay and -minrelaytxfee up or down as the memory pool grows or falls beyond one block in height.

A simple but effective way to block spammy transactions from getting accepted into the mempool and relayed, saving cpu, memory and valuable bandwidth.

The way it’s configured now it reaches maximum choke at 10 times the maximum block size.

When the mempool begins to fall again, the values of -minrelaytxfee and -limitfreerelay slowly return to their starting values using a 24hr decay.

morcos commented at 9:50 pm on October 10, 2015: member

There are a few things I don’t like about this implementation, such as starting the feeCutoff at 0 (instead of 1000 sat/kb). But I do think an approach like this would work to “solve” this problem in 0.10 and 0.11 backports. The problem with #6673 is there was no limit to how high the fee went, but if its capped at some value that is still potentially reasonable for a min relay fee (like in this pull), then it might be better than just changing a hard coded value.

ptschip commented at 10:25 pm on October 10, 2015: contributor

Starting the feeCutoff at 0 is easily changed, (we can start it anywhere ) but it does rise quite quickly once the mempool is full. When you compile and run use debug=mempool and the log entries show you how the values change as the mempool increases or decreases.

On 10/10/2015 2:50 PM, Alex Morcos wrote:

There are a few things I don’t like about this implementation, such as starting the feeCutoff at 0 (instead of 1000 sat/kb). But I do think an approach like this would work to “solve” this problem in 0.10 and 0.11 backports. The problem with #6673 #6673 is there was no limit to how high the fee went, but if its capped at some value that is still potentially reasonable for a min relay fee (like in this pull), then it might be better than just changing a hard coded value.

— Reply to this email directly or view it on GitHub #6803 (comment).

ptschip force-pushed on Oct 11, 2015

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TheBlueMatt commented at 10:03 am on October 14, 2015: member

I really prefer #6722 over this. It seems gratuitous to have a less-effecient implementation for mempool limiting unless we decide #6722 is overcomplicated or otherwise not mergedable.

morcos commented at 11:55 am on October 14, 2015: member

Oh I meant in consideration for a backport not for master.

Sent from my iPhone

On Oct 14, 2015, at 6:04 AM, Matt Corallo notifications@github.com wrote:

I really prefer #6722 over this. It seems gratuitous to have a less-effecient implementation for mempool limiting unless we decide #6722 is overcomplicated or otherwise not mergedable.

— Reply to this email directly or view it on GitHub.

ptschip force-pushed on Oct 14, 2015

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ptschip commented at 10:29 am on October 15, 2015: contributor

Here’s a plot of the last 12 hours showing the actual mempool size and cumulative blocked (spam) transactions over time (x axis in minutes, y axis in MiB).

mempool

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laanwj added the label TX fees and policy on Oct 26, 2015

Automatically adjusting Spam Block

Auto adjusts -limitfreerelay and
-minrelaytxfee up or down as the
memory pool grows or falls

b3b8df3134

ptschip force-pushed on Nov 4, 2015

gmaxwell commented at 11:00 pm on November 22, 2015: contributor

Closing this because I think it’s been eclipsed by the mempool limiting thats merged and the related fixes around it in the pipeline. If I’ve made an error, feel free to yell at me. :)

gmaxwell closed this on Nov 22, 2015

ptschip deleted the branch on Mar 7, 2016

MarcoFalke locked this on Sep 8, 2021

Automatically adjusting Spam Block #6803