107 sats \ 3 replies \ @spain 12 May 2022 \ on: How to prevent your low-fee transaction from being purged from the mempool bitcoin
No worries. I run some nodes with maxmempool=1000 and some with 2000. Also much raised maxorphantx and mempoolexpiry. And of course there are much more such higher-limit-nodes. And some even keep manually rebroadcasting each transaction in the big mempool they keep, like if it was comming from them using a script like following:
#!/bin/sh

USER=user:password_for_RPC_if_needed
TMPL=/tmp/mempool$$
trap "rm -rfv ${TMPL}*; exit 1" EXIT INT QUIT

printf "Preparing current mempool txid snapshot... "
bitcoin-cli getrawmempool \
  | sed '/^\[/d;/^\]/d;s/,$//;s/^  //;s/^"//;s/"$//' \
  | split -l 256 -a 5 - $TMPL \
  && echo done

ls $TMPL* >/dev/null 2>&1 \
  || { echo "Mempool empty. Sleeping."; sleep 60; exec $0; }

printf "Broadcasting: "
for file in $TMPL*; do
{ printf '['
  cat $file | while read tx
  do
    test -n "$tx" || continue
    RAW=$(bitcoin-cli getrawtransaction $tx 2>/dev/null) || continue
    printf '{"jsonrpc": "1.0", "id": "send", "method": "sendrawtransaction", "params": ["%s"]},' $RAW
  done
  printf '{"jsonrpc": "1.0", "id": "getbc", "method": "getblockcount", "params": []}]\n'
} | curl -s --user $USER --data-binary @- -H 'content-type: text/plain;' http://127.0.0.1:8332/ >/dev/null \
  && { rm $file && printf .; } \
  || { echo "ERR $file"; exit 1; }
done
echo done
sleep 20
exec $0
@k00b thanks, the indentation of the lines is fixed!
write
preview
19 sats \ 2 replies \ @o OP 12 May 2022
Thank you for sharing. And for maintaining these higher-limit-nodes. Also, damn—you're good at bash! I've learned a trick or two from this script :)
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12 sats \ 1 reply \ @Oszo3 12 May 2022
Happy you like it. It's actually bare POSIX shell free of any bashisms. This script runs with busybox ash and should run with OpenBSD's pdksh as well.
And @GDPR_deleted is not the author ;) The script is a public domain legacy.
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1 sat \ 0 replies \ @spain 13 May 2022
Old spoiler. Allow me at least one more day of fame next time please. Just kidding 😅
Yes, it's right.
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