v25.0rc2 unusably slow at times #27700

1. 
   dooglus commented at 5:38 pm on May 18, 2023: contributor

   Is there an existing issue for this?

   • I have searched the existing issues

   Current behaviour

   I’m testing v25.0rc2. Occasionally it becomes unresponsive. Simple requests like ‘getblockcount’ time out.

   I tried running in gdb to see where the code was getting hung up. It was loading the mempool.dat file, spending lots of time in CTxMemPool::addUnchecked(), running this line:

   vTxHashes.emplace_back(tx.GetWitnessHash(), newit);

   and also in CTxMemPool::TrimToSize().

   I added some LogPrintf() calls. It took 2380 seconds to load just 26 tx from the mempool.dat. That’s 91 seconds per tx. Here’s the relevant section of the debug.log.

   The issue only happens when the maxmempool value is reached, but that’s not enough to trigger it. The only time I’ve seen the issue happen is with the default 300 MB mempool limit. I tried using a 200 MB limit, but this issue didn’t happen. Then I set it back to the default 300 and now I can’t reproduce the issue.

   Expected behaviour

   I expect ‘getblockcount’ to be quick.

   Steps to reproduce

   I’m not able to reproduce.

   Relevant log output

   No response

   How did you obtain Bitcoin Core

   Compiled from source

   What version of Bitcoin Core are you using?

   v25.0rc2

   Operating system and version

   Debian GNU/Linux 11 (bullseye)

   Machine specifications

   Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz SSL disk Cable internet

2. 
   maflcko commented at 5:42 pm on May 18, 2023: member

   See https://github.com/bitcoin/bitcoin/issues/27586
3. 
   maflcko commented at 5:43 pm on May 18, 2023: member

   (I presume you run with --enable-debug, in which case you can work around by disabling that)
4. 
   dooglus commented at 7:26 pm on May 18, 2023: contributor

   @MarcoFalke Thanks. I use this:

   ./configure CXXFLAGS=-fno-omit-frame-pointer --with-incompatible-bdb --with-miniupnpc=no --enable-debug

   Closing the issue. And sorry for the dup.

5. dooglus closed this on May 18, 2023

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6. bitcoin locked this on May 17, 2024

Contributors
dooglus maflcko