nvme/perf: increase task pool size

This matches the size of the request pool and enables running with a
higher concurrency level.

Ideally, these limits should be calculated from the requested queue
depth and number of workers, but for now, just increase the hardcoded
limit.

Change-Id: I6e890efc78a1336dddc0ab61db20c68004b30f54
Signed-off-by: Daniel Verkamp <daniel.verkamp@intel.com>

examples/nvme/perf/perf.c

@@ -834,7 +834,7 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	task_pool = rte_mempool_create("task_pool", 2048,
+	task_pool = rte_mempool_create("task_pool", 8192,
 				       sizeof(struct perf_task),
 				       64, 0, NULL, NULL, task_ctor, NULL,
 				       SOCKET_ID_ANY, 0);