From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============2431297459632652230==" MIME-Version: 1.0 From: Walker, Benjamin Subject: Re: [SPDK] SPDK aio examples Date: Fri, 17 Jun 2016 17:24:47 +0000 Message-ID: <1466184287.26925.81.camel@intel.com> In-Reply-To: B4C78186-D836-4BB4-988C-44985BEBC049@playstation.sony.com List-ID: To: spdk@lists.01.org --===============2431297459632652230== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable On Wed, 2016-06-15 at 23:56 +0000, Bhadauria, Varun wrote: > Hello Ben > = > Thank you for the clarification. I was under the false impression that Li= nux AIO can be made to > use SPDK under the hood which is clearly not the case since they will hav= e to go through the > filesystem. = I'm sure someone could wrap the AIO interface around the SPDK driver for th= e specific case where the user is opening a block device directly with O_DIRECT. It's nearly a 1:1 tr= anslation for that case. Unfortunately, most people use Linux AIO on files instead of block devices. > BTW are there any known early filesystem implementation besides ceph=E2= =80=99s rocksdb based bluestore FS > which use SPDK. The only publicly announced one that I'm aware of is Bluestore inside of Ce= ph. As long as SPDK continues to be valuable, I fully expect many filesystems with different de= signs to appear over time. If you have a particular use case where you'd like some sort of files= ystem-like layer on top of SPDK, I'd love to hear about it. At a minimum, it's useful to collect re= quirements from a number of sources. > = > Regards, > Varun Bhadauria > =C2=A0 > = > On 6/15/16, 4:37 PM, "SPDK on behalf of Walker, Benjamin" benjamin.walker(a)intel.com> wrote: > = > > = > > Can you explain a bit more about why you want to use AIO? Are you refer= ring to Linux AIO or > > POSIX AIO? If you want to do a performance comparison of Linux AIO and = the SPDK NVMe driver then > > the perf tool is your best bet. > > = > > You can run the perf tool against a block device using Linux AIO by bin= ding your NVMe device to > > the kernel ("./scripts/setup.sh reset" will hand them all back to the k= ernel) and then doing > > something like: > > = > > ./perf -q 1 -s 4096 -w read -t 10 /dev/nvme0n1 /dev/nvme1n1 > > = > > -----Original Message----- > > From: SPDK [mailto:spdk-bounces(a)lists.01.org] On Behalf Of Bhadauria,= Varun > > Sent: Wednesday, June 15, 2016 4:30 PM > > To: Storage Performance Development Kit > > Subject: [SPDK] SPDK air examples > > = > > Hello=C2=A0 > > = > > Are there any SPDK examples which use AIO?=C2=A0=C2=A0Perf.c has very l= ittle documentation in the usage > > for AIO. > > = > > Regards, > > Varun Bhadauria > > = > > = > > _______________________________________________ > > SPDK mailing list > > SPDK(a)lists.01.org > > https://lists.01.org/mailman/listinfo/spdk > > _______________________________________________ > > SPDK mailing list > > SPDK(a)lists.01.org > > https://lists.01.org/mailman/listinfo/spdk > _______________________________________________ > SPDK mailing list > SPDK(a)lists.01.org > https://lists.01.org/mailman/listinfo/spdk --===============2431297459632652230==--