$vardir/state/o.<SID>-ops_cache may be corrupted due to disk failure or system i/o errors.
Solution:
1. Shutdown SharePlex on source
2. Rename $vardir/state/o.<SID>-ops_cache
3. Start sp_cop (e.g. ./sp_cop -u2100&)
If reader encounter the same error, please contact Quest Technical Support.