Doug Cutting wrote:
hairong Kuang wrote:
1. NNBench sets the block size to be 1. Althouth it generates a file with
only 1 byte, but the file's checksum file has 16 bytes (12 bytes header
plus 4 bytes checksums). Without the checksum file, only 1 block needs
to be
generated. With the checksum file, 17 blocks need to be generated. So the
overhead of generating a checksum file is huge in this special case.
So to make this benchmark more representative of real performance with
lots of small files, we should change the block size to 16 or greater.
While small files may be typical, a blocksize of 1 is not. Since the
benchmark only writes one byte per file, a tiny block size doesn't
really need to be set at all for this benchmark.
+1. I was thinking of the same. We could even leave the block size to
default and create 1 byte files as we do now.
Raghu.
Doug
