From: Vincent Fu <vincent.fu@xxxxxxx>
Especially with small sample spaces, the LFSR random generator
occasionally fails to initialize successfully. When this occurs, the
error message refers to problems allocating a random map. Change the
error message to explicitly mention the LFSR failure.
OLD BEHAVIOR
$ ./fio --name=test --ioengine=null --size=4k --random_generator=lfsr --rw=randread --randrepeat=0
test: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=null, iodepth=1
fio-3.16-13-g998b-dirty
Starting 1 process
fio: failed allocating random map. If running a large number of jobs, try the 'norandommap' option or set 'softrandommap'. Or give a larger --alloc-size to fio.
NEW BEHAVIOR
$ ./fio --name=test --ioengine=null --size=4k --random_generator=lfsr --rw=randread --randrepeat=0
test: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T) 4096B-4096B, ioengine=null, iodepth=1
fio-3.16-37-g65ee
Starting 1 process
fio: failed initializing LFSR
---
filesetup.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/filesetup.c b/filesetup.c
index 1d3094c1..7d54c9f1 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -1354,6 +1354,9 @@ bool init_random_map(struct thread_data *td)
if (!lfsr_init(&f->lfsr, blocks, seed, 0)) {
fio_file_set_lfsr(f);
continue;
+ } else {
+ log_err("fio: failed initializing LFSR\n");
+ return false;
}
} else if (!td->o.norandommap) {
f->io_axmap = axmap_new(blocks);
--
2.17.1
