Currently, each histogram range is hardcoded to
128 buckets (1ULL << 7), resulting in 58 ranges
(64 - 7 + 1) and a total size of 58 * 128 *
sizeof(uint64_t) = 59392 bytes.
To allow for more usage models in cases where this
size is prohibitive, enable the following changes:
1) specify number of buckets per range (in number of bits)
2) specify max datapoint value (in number of bits)
The latter can be useful for cases where datapoints
are never close to requiring all 64 bits - and allows
reducing the number of ranges. Any data points that
exceed the max will be tallied in the last bucket
in the last range.
Testing shows no performance disadvantage using the
dynamic approach.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I5979bcdff6209faaa9dee293918ef2a78679bcd4
Reviewed-on: https://review.gerrithub.io/392707
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
This simplifies some upcoming changes, where the
buckets will be a dynamically allocated array instead
of a static 2-dimensional array.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I3854319385937be9f9ace4be7dd22423e24f25e3
Reviewed-on: https://review.gerrithub.io/392706
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
No functional change - this just reduces the diff for
some upcoming changes.
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Ic185d32b38d5ccbc81cab49a6a38ebde0da71afd
Reviewed-on: https://review.gerrithub.io/392705
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: Ia0083365b2da63cb38aebb9f7bbc02f4dfd1ae94
Reviewed-on: https://review.gerrithub.io/365263
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
