On 08/04/2016 04:53 AM, Srinivasa Chamarthy wrote:
Tried the latest git, i do not get the failure now. But i have the following questions 1) The initial failure was due to the fact that there were no files in the directory to read. In that case, it may be expected that we write the files first and then do read (workload defaults to read if --rw is not specified).
Right, but that's similar to how a normal read job without create_on_open would also layout the files to be able to run the read workload.
2) For Write or mixed jobs, create_on_open is expected not to layout the IO files before the workload. Currently with the latest git, i see that it says that files are layed out (but the size is 0) before the workload starts. If i do not specify create_on_open, its not laying out files at all. And i have to specify create_on_open=0 explicitly to layout the files completely. With create_on_open=1 # fio --name=test --directory=/testdata --nrfiles=10 --size=1g --refill_buffers=1 --direct=1 --create_on_open=1 --rw=write test: (g=0): rw=write, bs=4K-4K/4K-4K/4K-4K, ioengine=psync, iodepth=1 fio-2.13-38-gff56 Starting 1 process test: Laying out IO file(s) (10 file(s) / 0MB) Jobs: 1 (f=10): [W(1)] [100.0% done] [0KB/5684KB/0KB /s] [0/1421/0 iops] [eta 00m:00s] Without create_on_open (No Initial layout of files) # fio --name=test --directory=/testdata --nrfiles=10 --size=1g --refill_buffers=1 --direct=1 --rw=write test: (g=0): rw=write, bs=4K-4K/4K-4K/4K-4K, ioengine=psync, iodepth=1 fio-2.13-38-gff56 Starting 1 process Jobs: 1 (f=10): [W(1)] [8.2% done] [0KB/6612KB/0KB /s] [0/1653/0 iops] [eta 02m:37s] With create_on_open=0 (its laying out files) # fio --name=test --directory=/testdata --nrfiles=10 --size=1g --refill_buffers=1 --direct=1 --rw=write --create_on_open=0 test: (g=0): rw=write, bs=4K-4K/4K-4K/4K-4K, ioengine=psync, iodepth=1 fio-2.13-38-gff56 Starting 1 process test: Laying out IO file(s) (10 file(s) / 1023MB) Jobs: 1 (f=10): [W(1)] [5.1% done] [0KB/6328KB/0KB /s] [0/1582/0 iops] [eta 02m:49s] Just wanted to get confirmation on what's the default behavior. I was under the impression that if create_on_open is not specified, default behavior is to layout the files for jobs.
Right, that was essentially the behaviour before the recent change. With the recent change, it'll lay them out if it needs to. It needs to, if the actual job doesn't do it, or if overwrite=1 is set, for instance, and it's a writable job. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
