Re: Error running Fio SSD example

["Georg Schönberger" <gschoenberger@thomas-krenn.com>]

Am 2012-06-08 20:44, schrieb Jens Axboe:
> On 2012-06-08 19:20, Georg Schï¿œnberger wrote:
>> Am 2012-06-08 14:47, schrieb Jens Axboe:
>>> On 06/01/2012 12:06 PM, Georg Schï¿œnberger wrote:
>>>> Hello again,
>>>>
>>>> I am having some troubles with running the fio example "ssd-test". I
>>>> changed the global section to decrease the size:
>>>> [global]
>>>> bs=4k
>>>> ioengine=libaio
>>>> iodepth=4
>>>> size=100M
>>>> direct=1
>>>> runtime=60
>>>> filename=ssd.test.file
>>>>
>>>> If I am running Fio I get the following error:
>>>> ----------------------------------------
>>>> fio.git/examples$ fio ssd-test
>>>> seq-read: (g=0): rw=read, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=4
>>>> rand-read: (g=1): rw=randread, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=4
>>>> seq-write: (g=2): rw=write, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=4
>>>> rand-write: (g=3): rw=randwrite, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=4
>>>> fio-2.0.8
>>>> Starting 4 processes
>>>> fio: pid=17997, err=22/file:filesetup.c:529, func=open(ssd.test.file),
>>>> error=Invalid argument
>>>> fio: pid=17998, err=22/file:filesetup.c:529, func=open(ssd.test.file),
>>>> error=Invalid argument
>>>> fio: pid=17999, err=22/file:filesetup.c:529, func=open(ssd.test.file),
>>>> error=Invalid argument
>>>> fio: pid=18000, err=22/file:filesetup.c:529, func=open(ssd.test.file),
>>>> error=Invalid argument
>>> Looks like the file system hosting the test file does not support
>>> O_DIRECT.
>>>
>> The file system is ext4.
>> Kernel Version 3.2.0-24-generic
> And you aren't running the job file in some other location? ext4 would
> definitely work. Please do:
>
> # strace -o strace.out -f fio ssd-test
>
> and send me strace.out (gzip'ed). Also include a pwd from where you are
> running it, and output of the 'mount' command.
>
Here is the solution to my problem (answered from Jens Axboe):
/ecryptfs does not support O_DIRECT IO. So that was the explanation for
the problem./

Also a patch so that FIO gives some further information now:
/Sure, I think it'd be a good idea if fio also complains that this is
the likely explanation. Fio does this if the first IO errors, but it
doesn't catch cases where O_DIRECT simply isn't supported. Can you try
this patch, see if it complains as it should?/

The patch has already been tested and commited (also from Jens):
diff --git a/filesetup.c b/filesetup.c
index a1ad026..b1f73f7 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -526,6 +526,11 @@ open_again:
 
         snprintf(buf, sizeof(buf) - 1, "open(%s)", f->file_name);
 
+        if (__e == EINVAL && (flags & OS_O_DIRECT)) {
+            log_err("fio: looks like your file system does not " \
+                "support direct=1/buffered=0\n");
+        }
+
         td_verror(td, __e, buf);
     }