Hi,
The unrv2b uncompression algorithm appears to behave very badly in the
absence of a proper cache. Instrumentation indicates somehting like ~180
i-stream cacheline requests for _every_ d-stream cacheline request
during decompression. The following patch copies the unrv2b function to
DRAM before performing the actual decompression, reducing the run-time
from 12.5s to 50ms in my environment. The patch is somewhat rough, and
assumes that (1) the unrv2b function is less than 1k in size, and (2)
that placing a copy of the function just after the decompress
destination is unproblematic. It works well for me, though.
Signed-off-by: Arne Georg Gleditsch <arne.gleditsch(a)numascale.com>
--
Arne.