You are conduction the benchmark on the Ceph OSD node itself. Some of those reads will be local and do not traverse the network.Why is there less network traffic when doing sequential reads compared to the Ceph read bandwidth?
You are conduction the benchmark on the Ceph OSD node itself. Some of those reads will be local and do not traverse the network.Why is there less network traffic when doing sequential reads compared to the Ceph read bandwidth?
The missing key in the your account details.- And why do I miss out on that paying customer batch???
Ceph is build with upstream defaults. You may try to use RDMA, but then we are not able to provide enterprise support to you.- Since we have Mellanox network cards and a Mellanox switch in place should I try out RDMA (https://community.mellanox.com/s/article/bring-up-ceph-rdma---developer-s-guide )? Is that supported now? Is it stable enough for production use?
You can also have a look with atop, it may give you greater detail then htop.Might be a good idea to repeat the test and use taskset to pin relevant processes to a number of CPU Cores to identify that one CPU hungry process.
The CPU architecture probably comes to play here. Since our Epyc only has 16c by 8 CCDs, a difference was not visible.The result is not as good as with 4 OSDs per NVMe. It seems the OSD is CPU-bound.
Hi , I have just nearly the same hardware.First test is to see if the network configuration is in order. 100GBit is 4 network streams combined, so at least 4 processes are required to test for the maximum.
Code:root@proxmox04:~# iperf -c 10.33.0.15 -P 4 ------------------------------------------------------------ Client connecting to 10.33.0.15, TCP port 5001 TCP window size: 325 KByte (default) ------------------------------------------------------------ [ 5] local 10.33.0.14 port 49772 connected with 10.33.0.15 port 5001 [ 4] local 10.33.0.14 port 49770 connected with 10.33.0.15 port 5001 [ 3] local 10.33.0.14 port 49768 connected with 10.33.0.15 port 5001 [ 6] local 10.33.0.14 port 49774 connected with 10.33.0.15 port 5001 [ ID] Interval Transfer Bandwidth [ 5] 0.0-10.0 sec 29.0 GBytes 24.9 Gbits/sec [ 4] 0.0-10.0 sec 28.9 GBytes 24.8 Gbits/sec [ 3] 0.0-10.0 sec 28.1 GBytes 24.1 Gbits/sec [ 6] 0.0-10.0 sec 28.9 GBytes 24.9 Gbits/sec [SUM] 0.0-10.0 sec 115 GBytes 98.7 Gbits/sec root@proxmox04:~#
Date and Time: 2020/10/15 16:00:25
Hostname: switch-a492f4
Uptime: 54m 24s
Software Version: X86_64 3.9.0300 2020-02-26 19:25:24 x86_64
Model: x86onie
Host ID: 0C42A1A492F4
System memory: 2193 MB used / 5610 MB free / 7803 MB total
CPU load averages: 3.02 / 3.06 / 3.01
System UUID 97828b5e-d1f2-11ea-8000-1c34daef9500
Client connecting to 10.101.200.131, TCP port 5001
TCP window size: 85.0 KByte (default)
------------------------------------------------------------
[ 4] local 10.101.200.132 port 54998 connected with 10.101.200.131 port 5001
[ 6] local 10.101.200.132 port 55002 connected with 10.101.200.131 port 5001
[ 3] local 10.101.200.132 port 54996 connected with 10.101.200.131 port 5001
[ 5] local 10.101.200.132 port 55000 connected with 10.101.200.131 port 5001
[ ID] Interval Transfer Bandwidth
[ 4] 0.0-10.0 sec 19.9 GBytes 17.1 Gbits/sec
[ 6] 0.0-10.0 sec 14.7 GBytes 12.6 Gbits/sec
[ 3] 0.0-10.0 sec 18.9 GBytes 16.3 Gbits/sec
[ 5] 0.0-10.0 sec 14.4 GBytes 12.4 Gbits/sec
[SUM] 0.0-10.0 sec 68.0 GBytes 58.4 Gbits/sec
root@pve02:~#
root@pve01:/usr/local/src/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64# ls -latrh
total 192K
drwxr-xr-x 2 root root 3 Sep 15 15:08 src
-rwxr-xr-x 1 root root 12K Sep 15 15:08 uninstall.sh
-rwxr-xr-x 1 root root 158K Sep 15 15:08 mlnxofedinstall
-rwxr-xr-x 1 root root 26K Sep 15 15:08 mlnx_add_kernel_support.sh
-rw-r--r-- 1 root root 12 Sep 15 15:08 .mlnx
-rw-r--r-- 1 root root 956 Sep 15 15:08 LICENSE
drwxr-xr-x 8 root root 12 Sep 15 15:08 docs
-rw-r--r-- 1 root root 11 Sep 15 15:08 distro
-rwxr-xr-x 1 root root 25K Sep 15 15:08 create_mlnx_ofed_installers.pl
-rwxr-xr-x 1 root root 8.1K Sep 15 15:08 common.pl
-rwxr-xr-x 1 root root 2.9K Sep 15 15:08 common_installers.pl
-rw-r--r-- 1 root root 7 Sep 15 15:08 .arch
-rw-r--r-- 1 root root 1.8K Sep 15 15:09 RPM-GPG-KEY-Mellanox
drwxr-xr-x 5 root root 16 Sep 15 15:09 .
drwxr-xr-x 2 root root 144 Sep 15 15:10 DEBS
drwxr-xr-x 3 root root 4 Oct 15 15:38 ..
root@pve01:/usr/local/src/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64# ./mlnxofedinstall
Error: The current MLNX_OFED_LINUX is intended for debian10.0
- Mellanox mft tools installieren und treiber kompilieren lassen
- Alte Version rausholen und dokumentieren (mlxburn -query -d /dev/mst/mt<TAB><TAB>)
- Neue Version einspielen (https://www.mellanox.com/support/firmware/connectx5en - OPN: MCX516A-CCAT <-- Über die PSID rausgefunden...)
- Es braucht einen Server Reboot, um die Firmware sauber upzugraden!!!
root@proxmox06:~# mlxburn -d /dev/mst/mt4119_pciconf0 -query
-I- Image type: FS4
-I- FW Version: 16.26.1040
-I- FW Release Date: 26.9.2019
-I- Product Version: 16.26.1040
-I- Rom Info: type=UEFI version=14.19.14 cpu=AMD64
-I- type=PXE version=3.5.803 cpu=AMD64
-I- Description: UID GuidsNumber
-I- Base GUID: 0c42a103002b02c4 8
-I- Base MAC: 0c42a12b02c4 8
-I- Image VSD: N/A
-I- Device VSD: N/A
-I- PSID: MT_0000000012
-I- Security Attributes: N/A
root@proxmox06:~#
root@proxmox06:~# flint -i fw-ConnectX5-rel-16_28_2006-MCX516A-CCA_Ax-UEFI-14.21.17-FlexBoot-3.6.102.bin -d /dev/mst/mt4119_pciconf0 burn
Current FW version on flash: 16.26.1040
New FW version: 16.28.2006
Initializing image partition - OK
Writing Boot image component - OK
-I- To load new FW run mlxfwreset or reboot machine.
root@proxmox06:~# flint -d /dev/mst/mt4119_pciconf0 query
Image type: FS4
FW Version: 16.28.2006
FW Version(Running): 16.26.1040
FW Release Date: 15.9.2020
Product Version: 16.26.1040
Rom Info: type=UEFI version=14.19.14 cpu=AMD64
type=PXE version=3.5.803 cpu=AMD64
Description: UID GuidsNumber
Base GUID: 0c42a103002b02c4 8
Base MAC: 0c42a12b02c4 8
Image VSD: N/A
Device VSD: N/A
PSID: MT_0000000012
Security Attributes: N/A
root@proxmox06:~#
Date and Time: 2020/10/15 16:12:14
Hostname: dc1-switch07
Uptime: 66d 16h 29m 47s
Software Version: X86_64 3.9.0612 2020-05-08 10:52:22 x86_64
Model: x86onie
Host ID: 98039BAE4C68
System memory: 2647 MB used / 5156 MB free / 7803 MB total
CPU load averages: 0.04 / 0.05 / 0.00
System UUID 355b9ae4-4051-11e9-8000-b8599f5c0f80
Could you please elaborate? I suppose it is not the one in your signature.Hi , I have just nearly the same hardware.
yep, signature is another cluster...Could you please elaborate? I suppose it is not the one in your signature.
3 nodes, pve 6.2.-1 iso install with all patches applied
supermicro 2113S-wn24rt
amd epyc 7502P 2,5Ghz 32c/64t
512GB mem ddr4-3200 cl22
2 samsung pm981 nvme m.2 (raid-1) system zfs
4 nvme 3,2tb samsung pm1725b 2,5'' U.2
dual port broadcom mcn57416 10GBase-T
dual port mellanox connect-x5 qsfp28
100GbE switch sn2100-cb2f
10GbE switch d-link dxs 1210-16tc
Is NUMA enabled in the BIOS? Certain BIOS settings will alter the node count.amd epyc 7502P 2,5Ghz 32c/64t
Since the Supermicro system uses RISER cards, is it situated/configured correctly?dual port mellanox connect-x5 qsfp28
I just found a way to accomplish firmware update, without messing with driver update not coming form proxmox repro!@Gerhard W. Recher , I documented that in German....
Code:- Mellanox mft tools installieren und treiber kompilieren lassen - Alte Version rausholen und dokumentieren (mlxburn -query -d /dev/mst/mt<TAB><TAB>) - Neue Version einspielen (https://www.mellanox.com/support/firmware/connectx5en - OPN: MCX516A-CCAT <-- Über die PSID rausgefunden...) - Es braucht einen Server Reboot, um die Firmware sauber upzugraden!!!
Alte Version
Code:root@proxmox06:~# mlxburn -d /dev/mst/mt4119_pciconf0 -query -I- Image type: FS4 -I- FW Version: 16.26.1040 -I- FW Release Date: 26.9.2019 -I- Product Version: 16.26.1040 -I- Rom Info: type=UEFI version=14.19.14 cpu=AMD64 -I- type=PXE version=3.5.803 cpu=AMD64 -I- Description: UID GuidsNumber -I- Base GUID: 0c42a103002b02c4 8 -I- Base MAC: 0c42a12b02c4 8 -I- Image VSD: N/A -I- Device VSD: N/A -I- PSID: MT_0000000012 -I- Security Attributes: N/A root@proxmox06:~#
Neue Version
Code:root@proxmox06:~# flint -i fw-ConnectX5-rel-16_28_2006-MCX516A-CCA_Ax-UEFI-14.21.17-FlexBoot-3.6.102.bin -d /dev/mst/mt4119_pciconf0 burn Current FW version on flash: 16.26.1040 New FW version: 16.28.2006 Initializing image partition - OK Writing Boot image component - OK -I- To load new FW run mlxfwreset or reboot machine. root@proxmox06:~# flint -d /dev/mst/mt4119_pciconf0 query Image type: FS4 FW Version: 16.28.2006 FW Version(Running): 16.26.1040 FW Release Date: 15.9.2020 Product Version: 16.26.1040 Rom Info: type=UEFI version=14.19.14 cpu=AMD64 type=PXE version=3.5.803 cpu=AMD64 Description: UID GuidsNumber Base GUID: 0c42a103002b02c4 8 Base MAC: 0c42a12b02c4 8 Image VSD: N/A Device VSD: N/A PSID: MT_0000000012 Security Attributes: N/A root@proxmox06:~#
Switch details (HPE SN2100M):
Code:Date and Time: 2020/10/15 16:12:14 Hostname: dc1-switch07 Uptime: 66d 16h 29m 47s Software Version: X86_64 3.9.0612 2020-05-08 10:52:22 x86_64 Model: x86onie Host ID: 98039BAE4C68 System memory: 2647 MB used / 5156 MB free / 7803 MB total CPU load averages: 0.04 / 0.05 / 0.00 System UUID 355b9ae4-4051-11e9-8000-b8599f5c0f80
Connection between Switch and NICs is done with DAC cables provided by FS.com.
I did not install the Mellanox Drivers, I am just using what is coming with ProxMox. Any recommendations on this, @Alwin ?
wget -qO - http://www.mellanox.com/downloads/ofed/RPM-GPG-KEY-Mellanox | apt-key add -
download package from mellanox
http://content.mellanox.com/ofed/MLNX_OFED-5.1-2.3.7.1/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64.tgz
/etc/apt/sources.list.d/mlnx_ofed.list
deb file:/usr/local/src/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64/DEBS ./
apt-get update
apt-get install mlnx-fw-updater <----- this will instantly run !
Initializing...
Attempting to perform Firmware update...
Querying Mellanox devices firmware ...
Device #1:
----------
Device Type: ConnectX5
Part Number: MCX516A-CCA_Ax
Description: ConnectX-5 EN network interface card; 100GbE dual-port QSFP28; PCIe3.0 x16; tall bracket; ROHS R6
PSID: MT_0000000012
PCI Device Name: 45:00.0
Base GUID: 506b4b0300f37ea0
Base MAC: 506b4bf37ea0
Versions: Current Available
FW 16.22.1002 16.28.2006
PXE 3.5.0403 3.6.0102
UEFI 14.15.0019 14.21.0017
Status: Update required
---------
Found 1 device(s) requiring firmware update...
Device #1: Updating FW
Restart needed for updates to take effect.
Log File: /tmp/mlnx_fw_update.log
Numa is on,Is NUMA enabled in the BIOS? Certain BIOS settings will alter the node count.
Since the Supermicro system uses RISER cards, is it situated/configured correctly?
lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
Address sizes: 43 bits physical, 48 bits virtual
CPU(s): 64
On-line CPU(s) list: 0-63
Thread(s) per core: 2
Core(s) per socket: 32
Socket(s): 1
NUMA node(s): 1
Vendor ID: AuthenticAMD
CPU family: 23
Model: 49
Model name: AMD EPYC 7502P 32-Core Processor
Stepping: 0
CPU MHz: 1733.730
CPU max MHz: 2500.0000
CPU min MHz: 1500.0000
BogoMIPS: 5000.28
Virtualization: AMD-V
L1d cache: 32K
L1i cache: 32K
L2 cache: 512K
L3 cache: 16384K
NUMA node0 CPU(s): 0-63
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate sme ssbd mba sev ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr wbnoinvd arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif umip rdpid overflow_recov succor smca
after firmware update of mellanox cards, still not near 100Gbit/sI just found a way to accomplish firmware update, without messing with driver update not coming form proxmox repro!
this is much more straight forward
Code:wget -qO - http://www.mellanox.com/downloads/ofed/RPM-GPG-KEY-Mellanox | apt-key add - download package from mellanox http://content.mellanox.com/ofed/MLNX_OFED-5.1-2.3.7.1/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64.tgz /etc/apt/sources.list.d/mlnx_ofed.list deb file:/usr/local/src/MLNX_OFED_LINUX-5.1-2.3.7.1-debian10.0-x86_64/DEBS ./ apt-get update apt-get install mlnx-fw-updater <----- this will instantly run ! Initializing... Attempting to perform Firmware update... Querying Mellanox devices firmware ... Device #1: ---------- Device Type: ConnectX5 Part Number: MCX516A-CCA_Ax Description: ConnectX-5 EN network interface card; 100GbE dual-port QSFP28; PCIe3.0 x16; tall bracket; ROHS R6 PSID: MT_0000000012 PCI Device Name: 45:00.0 Base GUID: 506b4b0300f37ea0 Base MAC: 506b4bf37ea0 Versions: Current Available FW 16.22.1002 16.28.2006 PXE 3.5.0403 3.6.0102 UEFI 14.15.0019 14.21.0017 Status: Update required --------- Found 1 device(s) requiring firmware update... Device #1: Updating FW Restart needed for updates to take effect. Log File: /tmp/mlnx_fw_update.log
iperf -c 10.101.200.131 -P 4 -e
------------------------------------------------------------
Client connecting to 10.101.200.131, TCP port 5001 with pid 5645
Write buffer size: 128 KByte
TCP window size: 85.0 KByte (default)
------------------------------------------------------------
[ 3] local 10.101.200.132 port 48008 connected with 10.101.200.131 port 5001
[ 4] local 10.101.200.132 port 48010 connected with 10.101.200.131 port 5001
[ 5] local 10.101.200.132 port 48012 connected with 10.101.200.131 port 5001
[ 6] local 10.101.200.132 port 48014 connected with 10.101.200.131 port 5001
[ ID] Interval Transfer Bandwidth Write/Err Rtry Cwnd/RTT
[ 3] 0.00-10.00 sec 18.5 GBytes 15.9 Gbits/sec 151493/0 45533 1314K/327 us
[ 4] 0.00-10.00 sec 18.1 GBytes 15.6 Gbits/sec 148536/0 47807 203K/84 us
[ 5] 0.00-10.00 sec 17.7 GBytes 15.2 Gbits/sec 144772/0 38680 246K/123 us
[ 6] 0.00-10.00 sec 17.8 GBytes 15.3 Gbits/sec 145577/0 38102 223K/84 us
[SUM] 0.00-10.00 sec 72.1 GBytes 61.9 Gbits/sec 590378/0 170122
my fault ... found it.... mtu was 1512 ... set to 9000....after firmware update of mellanox cards, still not near 100Gbit/s
Code:iperf -c 10.101.200.131 -P 4 -e ------------------------------------------------------------ Client connecting to 10.101.200.131, TCP port 5001 with pid 5645 Write buffer size: 128 KByte TCP window size: 85.0 KByte (default) ------------------------------------------------------------ [ 3] local 10.101.200.132 port 48008 connected with 10.101.200.131 port 5001 [ 4] local 10.101.200.132 port 48010 connected with 10.101.200.131 port 5001 [ 5] local 10.101.200.132 port 48012 connected with 10.101.200.131 port 5001 [ 6] local 10.101.200.132 port 48014 connected with 10.101.200.131 port 5001 [ ID] Interval Transfer Bandwidth Write/Err Rtry Cwnd/RTT [ 3] 0.00-10.00 sec 18.5 GBytes 15.9 Gbits/sec 151493/0 45533 1314K/327 us [ 4] 0.00-10.00 sec 18.1 GBytes 15.6 Gbits/sec 148536/0 47807 203K/84 us [ 5] 0.00-10.00 sec 17.7 GBytes 15.2 Gbits/sec 144772/0 38680 246K/123 us [ 6] 0.00-10.00 sec 17.8 GBytes 15.3 Gbits/sec 145577/0 38102 223K/84 us [SUM] 0.00-10.00 sec 72.1 GBytes 61.9 Gbits/sec 590378/0 170122
iperf -c 10.101.200.131 -P 4 -e
------------------------------------------------------------
Client connecting to 10.101.200.131, TCP port 5001 with pid 18556
Write buffer size: 128 KByte
TCP window size: 325 KByte (default)
------------------------------------------------------------
[ 3] local 10.101.200.132 port 48054 connected with 10.101.200.131 port 5001
[ 4] local 10.101.200.132 port 48056 connected with 10.101.200.131 port 5001
[ 5] local 10.101.200.132 port 48058 connected with 10.101.200.131 port 5001
[ 6] local 10.101.200.132 port 48060 connected with 10.101.200.131 port 5001
[ ID] Interval Transfer Bandwidth Write/Err Rtry Cwnd/RTT
[ 3] 0.00-10.00 sec 20.4 GBytes 17.5 Gbits/sec 166775/0 13650 428K/155 us
[ 4] 0.00-10.00 sec 22.7 GBytes 19.5 Gbits/sec 186223/0 14580 455K/190 us
[ 5] 0.00-10.00 sec 22.2 GBytes 19.1 Gbits/sec 182100/0 15059 376K/194 us
[ 6] 0.00-10.00 sec 21.4 GBytes 18.4 Gbits/sec 175001/0 14000 323K/136 us
[SUM] 0.00-10.00 sec 86.7 GBytes 74.5 Gbits/sec 710099/0 57289
root@pve02:~#
nope is not ... how to fix this ?74.5 Gbits/sec... - let's see your /proc/cmdline!
Check if "amd_iommu=on iommu=pt pcie_aspm=off" is already active!
BOOT_IMAGE=/ROOT/pve-1@/boot/vmlinuz-5.4.65-1-pve root=ZFS=rpool/ROOT/pve-1 ro root=ZFS=rpool/ROOT/pve-1 boot=zfs quiet
this was a match winner thx for your responses !Looks like you are booting using grub...
-> Adjust GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub
-> Run "update-grub"
-> Reboot
iperf -c 10.101.200.131 -P 4 -e
------------------------------------------------------------
Client connecting to 10.101.200.131, TCP port 5001 with pid 3252
Write buffer size: 128 KByte
TCP window size: 325 KByte (default)
------------------------------------------------------------
[ 6] local 10.101.200.132 port 48396 connected with 10.101.200.131 port 5001
[ 4] local 10.101.200.132 port 48392 connected with 10.101.200.131 port 5001
[ 3] local 10.101.200.132 port 48390 connected with 10.101.200.131 port 5001
[ 5] local 10.101.200.132 port 48394 connected with 10.101.200.131 port 5001
[ ID] Interval Transfer Bandwidth Write/Err Rtry Cwnd/RTT
[ 6] 0.00-10.00 sec 21.1 GBytes 18.1 Gbits/sec 172987/0 569 1960K/352 us
[ 4] 0.00-10.00 sec 38.1 GBytes 32.7 Gbits/sec 312323/0 751 1951K/268 us
[ 3] 0.00-10.00 sec 17.8 GBytes 15.3 Gbits/sec 146109/0 671 1137K/306 us
[ 5] 0.00-10.00 sec 38.2 GBytes 32.8 Gbits/sec 312783/0 837 1846K/155 us
[SUM] 0.00-10.00 sec 115 GBytes 99.0 Gbits/sec 944202/0 2828
root@pve02:~#
net.ipv4.tcp_timestamps=0
#2. Enable the TCP selective acks option for better throughput:
net.ipv4.tcp_sack=1
#3. Increase the maximum length of processor input queues:
net.core.netdev_max_backlog=250000
#4. Increase the TCP maximum and default buffer sizes using setsockopt():
net.core.rmem_max=4194304
net.core.wmem_max=4194304
net.core.rmem_default=4194304
net.core.wmem_default=4194304
net.core.optmem_max=4194304
#5. Increase memory thresholds to prevent packet dropping:
net.ipv4.tcp_rmem="4096 87380 4194304"
net.ipv4.tcp_wmem="4096 65536 4194304"
#6. Enable low latency mode for TCP:
net.ipv4.tcp_low_latency=1
#The following variable is used to tell the kernel how much of the socket buffer space should be used for TCP window size, and how much to save for an application buffer.
net.ipv4.tcp_adv_win_scale=1
#A value of 1 means the socket buffer will be divided evenly between TCP windows size and application.
ethtool -G enp69s0f0 rx 8192 tx 8192
ethtool -G enp69s0f1 rx 8192 tx 8192
# https://fasterdata.es.net/host-tuning/linux/100g-tuning/
# allow testing with buffers up to 512MB
net.core.rmem_max = 536870912
net.core.wmem_max = 536870912
# increase Linux autotuning TCP buffer limit to 256MB
net.ipv4.tcp_rmem = 4096 87380 268435456
net.ipv4.tcp_wmem = 4096 65536 268435456
# recommended default congestion control is htcp
#net.ipv4.tcp_congestion_control=htcp
# recommended for hosts with jumbo frames enabled
net.ipv4.tcp_mtu_probing=1
# recommended for CentOS7+/Debian8+ hosts
#net.core.default_qdisc = fq