...
If the object is replicated wholly, policy.ecEncoding is specified, and the object size is greater than the policy.ecMinStreamSize value, the object will be is converted to erasure coding. This implicit conversion occurs because of your cluster settings. Implicit conversions are used to convert legacy data—perhaps without lifepoints—to the default cluster encoding scheme, enabling legacy data to take advantage of the new capability. However, if the object is replicated and policy.ecEncoding is not configured or the object size is less than the policy.ecMinStreamSize value, the object remains replicated at scsp.defreps replicas.
The Health Processor converts these objects at a slower rate than the next Health Processor cycle to balance its processing cycles between object conversions and other system requirements. The ec.conversionPercentage setting governs the conversion rate. The ec.conversionPercentage setting defaults to zero, which implies no implicit conversion. Until the object is converted, it will be is replicated with scsp.defreps reps.
...
When the Health Processor converts objects from standard replication to erasure coding, it replaces the Etag and the Castor-System-Version header. When the if-match and if-none-match cache coherency headers compare the request header content against the Castor-System-Created header on the object (which does not change during the conversion), the headers will believe the object has changed, even though the content data is actually the same. The cache coherency headers will do not always behave as expected.
...