Go back to params that provide better cratios in general

Blosc · Jan 21, 2025 · d65eeb7 · d65eeb7
1 parent 07a76d1
commit d65eeb7
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/blosc/blosclz.c b/blosc/blosclz.c
@@ -429,14 +429,15 @@ int blosclz_compress(const int clevel, const void* input, int length,
    * It looks like 4 is more useful in combination with bitshuffle and small typesizes
    * Fallback to 4 because it provides more consistent results for large cratios.
    * UPDATE: new experiments show that using a value of 3 is a bit better, at least for ERA5.
+   * UPDATE 2: go back to 4, as they seem to provide better cratios in general.
    *
    * In this block we also check cratios for the beginning of the buffers and
    * eventually discard those that are small (take too long to decompress).
    * This process is called _entropy probing_.
    */
-  unsigned ipshift = 3;
+  unsigned ipshift = 4;
   // Minimum lengths for encoding (normally it is good to match the shift value)
-  unsigned minlen = 3;
+  unsigned minlen = 4;
 
   uint8_t hashlog_[10] = {0, HASH_LOG - 2, HASH_LOG - 1, HASH_LOG, HASH_LOG,
                           HASH_LOG, HASH_LOG, HASH_LOG, HASH_LOG, HASH_LOG};