Revert "Revert "blob: switched to adaptive mutexes when available""

This reverts commit 17cad75c7b7bf30f6fde6427dc460008e1514bba.
Revert "Revert "bloom: reworked bloom filter""

This reverts commit e4bdf8f65eeab968a2771b3d3c2622bdefee2761.
v0.19.7