Add option for io_limit
'size' denotes both the size of the region for IO, as well as the
amount of IO to transfer. Sometimes it's useful to be able to set
them separately instead. With this patch, you can do:
size=100G
io_limit=10G
and have fio do 10G of IO between 0..100G of the address space.
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/backend.c b/backend.c
index 12e562b..e0f8aa7 100644
--- a/backend.c
+++ b/backend.c
@@ -645,7 +645,7 @@
static int io_bytes_exceeded(struct thread_data *td)
{
- unsigned long long bytes;
+ unsigned long long bytes, limit;
if (td_rw(td))
bytes = td->this_io_bytes[DDIR_READ] + td->this_io_bytes[DDIR_WRITE];
@@ -656,7 +656,12 @@
else
bytes = td->this_io_bytes[DDIR_TRIM];
- return bytes >= td->o.size || exceeds_number_ios(td);
+ if (td->o.io_limit)
+ limit = td->o.io_limit;
+ else
+ limit = td->o.size;
+
+ return bytes >= limit || exceeds_number_ios(td);
}
/*
@@ -1141,6 +1146,8 @@
static int keep_running(struct thread_data *td)
{
+ unsigned long long limit;
+
if (td->done)
return 0;
if (td->o.time_based)
@@ -1152,14 +1159,19 @@
if (exceeds_number_ios(td))
return 0;
- if (td->o.size != -1ULL && ddir_rw_sum(td->io_bytes) < td->o.size) {
+ if (td->o.io_limit)
+ limit = td->o.io_limit;
+ else
+ limit = td->o.size;
+
+ if (limit != -1ULL && ddir_rw_sum(td->io_bytes) < limit) {
uint64_t diff;
/*
* If the difference is less than the minimum IO size, we
* are done.
*/
- diff = td->o.size - ddir_rw_sum(td->io_bytes);
+ diff = limit - ddir_rw_sum(td->io_bytes);
if (diff < td_max_bs(td))
return 0;