I have been alerted that certain classes of system continue to experience extremely low primespersec values. Upon investigation it seems certain systems have performance problems with the sieve, causing extended sieve round time. A temporary fix is now pushed to github. Please note I don't have enough time yet to fully test this solution, so try it out first to see if this resolves your system's problems.
https://github.com/primecoin/primecoin/commit/338e61568a32e74fa112edf1f3d8eee8d6780ae9
Please report back if this resolves your performance issues.
Update (July 14):
More sieve optimization:
https://github.com/primecoin/primecoin/commit/ab9fe91d711c92527fcde2fa34563b0aefd16742
Topic: [XPM] Primecoin Built-in Miner Sieve Performance Issue - page 38. (Read 69167 times)
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