What does "keypool reserve" & "keypool return" in the debug log indicate?

[DeathAndTaxes]

What does "keypool reserve" & "keypool return" in the debug log indicate?

2014-05-26 16:34:01 keypool reserve 9028
2014-05-26 16:34:01 keypool return 9028
2014-05-26 16:34:01 keypool reserve 9028
2014-05-26 16:34:01 keypool return 9028

[1715672180]

1715672180

[1715672180]

1715672180

[telepatheic]

They indicate that a key has been temporarily removed from the pool and then returned to the pool while an operation involving it is taking place. See the wallet.cpp file.

These functions allow multi-threading (two threads can't be using the same key at the same time).

[DeathAndTaxes]

Thanks and that opens up even more questions.  Not sure why a key would be removed from the keypool and returned.  Will need to dig into the code.