From: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> 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. Here are the results of some performance tests I ran on my own virtual machines, which does still have the slow SEEK_HOLE/SEEK_DATA behavior. A recent minimum-compiler-version patch makes installing newer kernels difficult on the lab machines I have access to, but I'll still try to collect that data since it seemed promising during my last posting (https://www.spinics.net/lists/linux-nfs/msg76488.html). I tested by reading various 2G files from a few different underlying 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 has 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. | v3 | v4.0 | v4.1 | v4.2 | ext4 | uncached: cached | uncached: cached | uncached: cached | uncached: cached | ----------|-------------------|-------------------|-------------------|-------------------| data | 2.697 : 1.365 | 2.539 : 1.482 | 2.246 : 1.595 | 2.516 : 1.716 | hole | 2.389 : 1.480 | 1.692 : 1.444 | 1.904 : 1.539 | 1.042 : 1.005 | mixed-4d | 2.426 : 1.448 | 2.468 : 1.480 | 2.258 : 1.731 | 2.408 : 1.674 | mixed-8d | 2.446 : 1.592 | 2.497 : 1.523 | 2.240 : 1.736 | 2.179 : 1.547 | mixed-16d | 2.608 : 1.575 | 2.446 : 1.582 | 2.330 : 1.670 | 2.192 : 1.488 | mixed-32d | 2.544 : 1.587 | 2.164 : 1.499 | 2.076 : 1.452 | 1.982 : 1.346 | mixed-4h | 2.591 : 1.486 | 2.233 : 1.503 | 2.190 : 1.520 | 3.679 : 1.815 | mixed-8h | 2.498 : 1.547 | 2.168 : 1.510 | 2.098 : 1.511 | 2.815 : 1.484 | mixed-16h | 2.480 : 1.664 | 2.152 : 1.597 | 2.096 : 1.537 | 2.288 : 1.580 | mixed-32h | 2.520 : 1.467 | 2.171 : 1.496 | 2.246 : 1.593 | 2.066 : 1.389 | | v3 | v4.0 | v4.1 | v4.2 | xfs | uncached: cached | uncached: cached | uncached: cached | uncached: cached | ----------|-------------------|-------------------|-------------------|-------------------| data | 2.074 : 1.353 | 2.129 : 1.489 | 2.198 : 1.564 | 2.579 : 1.719 | hole | 1.714 : 1.430 | 1.647 : 1.440 | 1.748 : 1.464 | 1.019 : 1.028 | mixed-4d | 2.699 : 1.561 | 2.782 : 1.657 | 2.800 : 1.619 | 2.848 : 2.166 | mixed-8d | 2.204 : 1.540 | 2.346 : 1.595 | 2.356 : 1.589 | 2.335 : 1.809 | mixed-16d | 2.034 : 1.445 | 2.212 : 1.561 | 2.172 : 1.546 | 2.127 : 1.658 | mixed-32d | 1.982 : 1.480 | 2.135 : 1.544 | 2.136 : 1.565 | 2.024 : 1.555 | mixed-4h | 2.600 : 1.549 | 2.790 : 1.660 | 2.745 : 1.634 | 8.949 : 2.529 | mixed-8h | 2.283 : 1.555 | 2.414 : 1.605 | 2.373 : 1.607 | 5.626 : 2.015 | mixed-16h | 2.115 : 1.512 | 2.247 : 1.593 | 2.217 : 1.608 | 3.740 : 1.803 | mixed-32h | 2.069 : 1.499 | 2.212 : 1.582 | 2.235 : 1.631 | 2.819 : 1.542 | | v3 | v4.0 | v4.1 | v4.2 | btrfs | uncached: cached | uncached: cached | uncached: cached | uncached: cached | ----------|-------------------|-------------------|-------------------|-------------------| data | 2.417 : 1.317 | 2.095 : 1.445 | 2.145 : 1.523 | 2.615 : 1.713 | hole | 2.107 : 1.483 | 2.121 : 1.496 | 2.106 : 1.461 | 1.011 : 1.061 | mixed-4d | 2.348 : 1.471 | 2.370 : 1.523 | 2.379 : 1.499 | 3.028 : 225.812 | mixed-8d | 2.227 : 1.476 | 2.231 : 1.467 | 2.272 : 1.529 | 2.723 : 36.179 | mixed-16d | 2.175 : 1.460 | 2.208 : 1.457 | 2.200 : 1.464 | 2.526 : 10.371 | mixed-32d | 2.148 : 1.501 | 2.191 : 1.468 | 2.167 : 1.471 | 2.455 : 3.367 | mixed-4h | 2.362 : 1.561 | 2.387 : 1.513 | 2.352 : 1.536 | 5.935 : 41.494 | mixed-8h | 2.241 : 1.477 | 2.251 : 1.503 | 2.256 : 1.496 | 3.672 : 10.261 | mixed-16h | 2.238 : 1.477 | 2.188 : 1.496 | 2.183 : 1.503 | 2.955 : 3.809 | mixed-32h | 2.146 : 1.490 | 2.135 : 1.523 | 2.157 : 1.557 | 2.327 : 2.088 | Anna Schumaker (10): SUNRPC: Split out a function for setting current page SUNRPC: Implement a xdr_page_pos() function NFS: Use xdr_page_pos() in NFSv4 decode_getacl() NFS: Add READ_PLUS data segment support SUNRPC: Split out xdr_realign_pages() from xdr_align_pages() SUNRPC: Split out _shift_data_right_tail() SUNRPC: Add the ability to expand holes in data pages NFS: Add READ_PLUS hole segment decoding SUNRPC: Add an xdr_align_data() function NFS: Decode a full READ_PLUS reply fs/nfs/nfs42xdr.c | 163 ++++++++++++++++++++ fs/nfs/nfs4proc.c | 43 +++++- fs/nfs/nfs4xdr.c | 7 +- include/linux/nfs4.h | 2 +- include/linux/nfs_fs_sb.h | 1 + include/linux/nfs_xdr.h | 2 +- include/linux/sunrpc/xdr.h | 5 + net/sunrpc/xdr.c | 308 ++++++++++++++++++++++++++++++++----- 8 files changed, 482 insertions(+), 49 deletions(-) -- 2.27.0
