Add options to have fio latency profile a device
This adds three new options:
- latency_target. This defines a specific latency target, in usec.
- latency_window. This defines the period over which fio samples.
- latency_percentile. This defines the percentage of IOs that must
meet the criteria specified by latency_target/latency_window.
With these options set, fio will run the described workload and
vary the queue depth between 1 and iodepth= to find the best
performing spot that meets the criteria specified by the three
options.
A sample job file is also added to demonstrate how to use this.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/thread_options.h b/thread_options.h
index 44cbf91..7476d8c 100644
--- a/thread_options.h
+++ b/thread_options.h
@@ -240,6 +240,10 @@
unsigned long long number_ios;
unsigned int sync_file_range;
+
+ unsigned long long latency_target;
+ unsigned long long latency_window;
+ fio_fp64_t latency_percentile;
};
#define FIO_TOP_STR_MAX 256
@@ -446,6 +450,10 @@
uint64_t number_ios;
uint32_t sync_file_range;
+
+ uint64_t latency_target;
+ uint64_t latency_window;
+ fio_fp64_t latency_percentile;
} __attribute__((packed));
extern void convert_thread_options_to_cpu(struct thread_options *o, struct thread_options_pack *top);