Dell EMC VxFlex Ready Node - Jumbo Frames and the Potential Impact on Performance

2. Set the RFcache parameters (Recommendation: these parameters have a great
impact on performance, therefore use the defaults).
scli --set_rfcache_parameters --protection_domain_name <domain
NAME> --rfcache_pass_through_mode pass_through_write_miss
Note: The default settings are; Passthrough mode = Write_Miss, Page Size 64
KB, Max IO size 128 KB.
3. Enable acceleration of a Storage Pool—accelerate all SDS devices that are in the
pool:
scli --set_rfcache_usage --protection_domain_name <domain
NAME> --storage_pool_name <pool NAME> --use_rfcache
For Read Flash Cache, the available modes are as follows:
l
pass_through_none
l
pass_through_read
l
pass_through_write
l
pass_through_read_and_write
l
pass_through_write_miss
The default caching mode is “write-miss”. In this mode, it is essentially a write-
through option where only reads and updates are cached. This mode buffers writes to
the data that was already in cache.
For more information related to using and configuring Read Flash Cache, refer to the
VxFlex OS Deployment Guide and VxFlex OS User Guide at https://support.emc.com.
Jumbo Frames and the potential impact on performance
When enabling jumbo frames, one can expect approximately 10% improvement in
performance if all network components fully support jumbo frames. If some network
components do not fully support jumbo frames, it is recommended to use the default
setting; mtu 1,500.
Prior to activating mtu settings on the logical level, set Jumbo frames = mtu 9000 on
the physical switch ports that are connected to the server. Failure to do so may lead
to network “disconnects” and packet drops.
Refer to your relevant vendor guidelines on how to configure jumbo frame support.
Jumbo Frame configuration for Linux
Configure Jumbo Frames for NIC cards in the Linux-based VxFlex OS servers.
About this task
Perform the following steps, for all the NIC cards in the VxFlex OS system:
Procedure
1. Run the ifconfig command to get the NIC information.
2. Depending on the OS, run the command:
VxFlex OS performance fine-tuning
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