Received-SPF: pass (google.com: best guess record for domain of linux-nfs-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   schumaker.anna@gmail.com
To:     Trond.Myklebust@hammerspace.com, linux-nfs@vger.kernel.org
Cc:     Anna.Schumaker@Netapp.com
Subject: [PATCH v2 0/6] NFS: Add support for the v4.2 READ_PLUS operation
Date:   Fri, 14 Feb 2020 16:12:21 -0500
Message-Id: <20200214211227.407836-1-Anna.Schumaker@Netapp.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-nfs-owner@vger.kernel.org
Precedence: bulk

From: Anna Schumaker <Anna.Schumaker@Netapp.com>

These patches add client support for the READ_PLUS operation, which
breaks read requests into several "data" and "hole" segments when
replying to the client. I also add a "noreadplus" mount option to allow
users to disable the new operation if it becomes a problem, similar to
the "nordirplus" mount option that we already have.

Here are the results of some performance tests I ran on Netapp lab
machines. I tested by reading various 2G files from a few different
undelying filesystems and across several NFS versions. I used the
`vmtouch` utility to make sure files were only cached when we wanted
them to be. In addition to 100% data and 100% hole cases, I also tested
with files that alternate between data and hole segments. These files
have either 4K, 8K, 16K, or 32K segment sizes and start with either data
or hole segments. So the file mixed-4d has a 4K segment size beginning
with a data segment, but mixed-32h hase 32K segments beginning with a
hole. The units are in seconds, with the first number for each NFS
version being the uncached read time and the second number is for when
the file is cached on the server.

ext4      |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 22.909 : 18.253 | 22.934 : 18.252 | 22.902 : 18.253 | 23.485 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.708 :  0.709 |
mixed-4d  | 28.261 : 18.253 | 29.616 : 18.252 | 28.341 : 18.252 | 24.508 :  9.150 |
mixed-8d  | 27.956 : 18.253 | 28.404 : 18.252 | 28.320 : 18.252 | 23.967 :  9.140 |
mixed-16d | 28.172 : 18.253 | 27.946 : 18.252 | 27.627 : 18.252 | 23.043 :  9.134 |
mixed-32d | 25.350 : 18.253 | 24.406 : 18.252 | 24.384 : 18.253 | 20.698 :  9.132 |
mixed-4h  | 28.913 : 18.253 | 28.564 : 18.252 | 27.996 : 18.252 | 21.837 :  9.150 |
mixed-8h  | 28.625 : 18.253 | 27.833 : 18.252 | 27.798 : 18.253 | 21.710 :  9.140 |
mixed-16h | 27.975 : 18.253 | 27.662 : 18.252 | 27.795 : 18.253 | 20.585 :  9.134 |
mixed-32h | 25.958 : 18.253 | 25.491 : 18.252 | 24.856 : 18.252 | 21.018 :  9.132 |

xfs       |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 22.041 : 18.253 | 22.618 : 18.252 | 23.067 : 18.253 | 23.496 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.723 :  0.708 |
mixed-4d  | 29.417 : 18.253 | 28.503 : 18.252 | 28.671 : 18.253 | 24.957 :  9.150 |
mixed-8d  | 29.080 : 18.253 | 29.401 : 18.252 | 29.251 : 18.252 | 24.625 :  9.140 |
mixed-16d | 27.638 : 18.253 | 28.606 : 18.252 | 27.871 : 18.253 | 25.511 :  9.135 |
mixed-32d | 24.967 : 18.253 | 25.239 : 18.252 | 25.434 : 18.252 | 21.728 :  9.132 |
mixed-4h  | 34.816 : 18.253 | 36.243 : 18.252 | 35.837 : 18.252 | 32.332 :  9.150 |
mixed-8h  | 43.469 : 18.253 | 44.009 : 18.252 | 43.810 : 18.253 | 37.962 :  9.140 |
mixed-16h | 29.280 : 18.253 | 28.563 : 18.252 | 28.241 : 18.252 | 22.116 :  9.134 |
mixed-32h | 29.428 : 18.253 | 29.378 : 18.252 | 28.808 : 18.253 | 27.378 :  9.134 |

btrfs     |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 25.547 : 18.253 | 25.053 : 18.252 | 24.209 : 18.253 | 32.121 : 18.253 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.252 |  0.702 :  0.724 |
mixed-4d  | 19.016 : 18.253 | 18.822 : 18.252 | 18.955 : 18.253 | 18.697 :  9.150 |
mixed-8d  | 19.186 : 18.253 | 19.444 : 18.252 | 18.841 : 18.253 | 18.452 :  9.140 |
mixed-16d | 18.480 : 18.253 | 19.010 : 18.252 | 19.167 : 18.252 | 16.000 :  9.134 |
mixed-32d | 18.635 : 18.253 | 18.565 : 18.252 | 18.550 : 18.252 | 15.930 :  9.132 |
mixed-4h  | 19.079 : 18.253 | 18.990 : 18.252 | 19.157 : 18.253 | 27.834 :  9.150 |
mixed-8h  | 18.613 : 18.253 | 19.234 : 18.252 | 18.616 : 18.253 | 20.177 :  9.140 |
mixed-16h | 18.590 : 18.253 | 19.221 : 18.252 | 19.654 : 18.253 | 17.273 :  9.135 |
mixed-32h | 18.768 : 18.253 | 19.122 : 18.252 | 18.535 : 18.252 | 15.791 :  9.132 |

ext3      |        v3       |       v4.0      |       v4.1      |       v4.2      |
----------|-----------------|-----------------|-----------------|-----------------|
data      | 34.292 : 18.253 | 33.810 : 18.252 | 33.450 : 18.253 | 33.390 : 18.254 |
hole      | 18.256 : 18.253 | 18.255 : 18.252 | 18.256 : 18.253 |  0.718 :  0.728 |
mixed-4d  | 46.818 : 18.253 | 47.140 : 18.252 | 48.385 : 18.253 | 42.887 :  9.150 |
mixed-8d  | 58.554 : 18.253 | 59.277 : 18.252 | 59.673 : 18.253 | 56.760 :  9.140 |
mixed-16d | 44.631 : 18.253 | 44.291 : 18.252 | 44.729 : 18.253 | 40.237 :  9.135 |
mixed-32d | 39.110 : 18.253 | 38.735 : 18.252 | 38.902 : 18.252 | 35.270 :  9.132 |
mixed-4h  | 56.396 : 18.253 | 56.387 : 18.252 | 56.573 : 18.253 | 67.661 :  9.150 |
mixed-8h  | 58.483 : 18.253 | 58.484 : 18.252 | 59.099 : 18.253 | 77.958 :  9.140 |
mixed-16h | 42.511 : 18.253 | 42.338 : 18.252 | 42.356 : 18.252 | 51.805 :  9.135 |
mixed-32h | 38.419 : 18.253 | 38.504 : 18.252 | 38.643 : 18.252 | 40.411 :  9.132 |


Changes since v1:
- Rebase to 5.6-rc1
- Drop the mount option patch for now
- Fix fallback to READ when the server doesn't support READ_PLUS

Any questions?
Anna


Anna Schumaker (6):
  SUNRPC: Split out a function for setting current page
  SUNRPC: Add the ability to expand holes in data pages
  SUNRPC: Add the ability to shift data to a specific offset
  NFS: Add READ_PLUS data segment support
  NFS: Add READ_PLUS hole segment decoding
  NFS: Decode multiple READ_PLUS segments

 fs/nfs/nfs42xdr.c          | 169 +++++++++++++++++++++++++
 fs/nfs/nfs4proc.c          |  43 ++++++-
 fs/nfs/nfs4xdr.c           |   1 +
 include/linux/nfs4.h       |   2 +-
 include/linux/nfs_fs_sb.h  |   1 +
 include/linux/nfs_xdr.h    |   2 +-
 include/linux/sunrpc/xdr.h |   2 +
 net/sunrpc/xdr.c           | 244 ++++++++++++++++++++++++++++++++++++-
 8 files changed, 457 insertions(+), 7 deletions(-)

-- 
2.25.0