debug.log
2021-05-05T15:21:06Z Config file arg: dbcache="0"
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2021-05-05T15:15:19Z * Using 0.5 MiB for block index database
2021-05-05T15:15:19Z * Using 1.8 MiB for chain state database
2021-05-05T15:15:19Z * Using 1.8 MiB for in-memory UTXO set (plus up to 286.1 MiB of unused mempool space)
-snip-'0' is an invalid value for database cache, the minimum is '4',
and in the process, your node configured a very low
in-memory UTXO set database size.
Nicehash transactions are usually large in size because of batching and that may be the reason for the crash.
You can try setting
dbcache to a high value, I'd suggest a quarter to half of your maximum RAM (
depending on your typical usage).