Change default IO engine from sync to psync

If the OS doesn't give us a default IO engine, then fio defaults to
sync. We should use psync instead, since we have that everywhere.
For fast storage, it avoids and lseek(), which can be a big deal.

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/os/os.h b/os/os.h
index 02ab40d38a6ca86c3b70552f797a1c6b9b28def7..98773838cb1a042df847505c7029cce04ae8fba4 100644 (file)
--- a/os/os.h
+++ b/os/os.h
@@ -151,7 +151,7 @@ extern int fio_cpus_split(os_cpu_mask_t *mask, unsigned int cpu);
 #endif
 
 #ifndef FIO_PREFERRED_ENGINE
-#define FIO_PREFERRED_ENGINE   "sync"
+#define FIO_PREFERRED_ENGINE   "psync"
 #endif
 
 #ifndef FIO_OS_PATH_SEPARATOR