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| author | Yuriy Andamasov <yuriy@vyos.io> | 2026-05-06 23:24:45 +0300 |
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| committer | Yuriy Andamasov <yuriy@vyos.io> | 2026-05-06 23:24:45 +0300 |
| commit | 89f86b481456437f3e9f16895e7408fe460de3f3 (patch) | |
| tree | f1bb09b203d56234c4518e6ab2d7fa5ca8610dec /docs/vpp/configuration/dataplane/memory.md | |
| parent | 6ce9145fa101e623c61f009c9cf5bb75a8a4a108 (diff) | |
| parent | 7cf51e1c2901f6d1b01e9bff194f7188bc29e417 (diff) | |
| download | vyos-documentation-89f86b481456437f3e9f16895e7408fe460de3f3.tar.gz vyos-documentation-89f86b481456437f3e9f16895e7408fe460de3f3.zip | |
Merge remote-tracking branch 'origin/current' into feat/docs-llms-txt-current
# Conflicts:
# docs/conf.py
Diffstat (limited to 'docs/vpp/configuration/dataplane/memory.md')
| -rw-r--r-- | docs/vpp/configuration/dataplane/memory.md | 142 |
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diff --git a/docs/vpp/configuration/dataplane/memory.md b/docs/vpp/configuration/dataplane/memory.md new file mode 100644 index 00000000..2465e3b3 --- /dev/null +++ b/docs/vpp/configuration/dataplane/memory.md @@ -0,0 +1,142 @@ +--- +lastproofread: '2026-02-27' +--- + +(vpp_config_dataplane_memory)= + +```{include} /_include/need_improvement.txt +``` + +# VPP Memory Configuration + +VPP heavily relies on hugepages for its memory management. Hugepages +are larger memory pages that reduce the overhead of page management and +improve performance for applications that require large amounts of +memory, such as VPP. + +VPP supports both 2MB and 1GB hugepages, but the default and most +commonly used size is 2MB. The choice of hugepage size can impact +performance, with larger pages generally providing better performance +for memory-intensive applications. + +Before configuring memory in VPP dataplane settings, you need to +ensure that hugepages are enabled and properly configured on your +system. + +:::{seealso} +{ref}`Hugepages in VyOS Configuration for VPP <vpp-config-hugepages>` +::: + +To configure memory settings for VPP, you can use the following +commands in the VPP CLI: + +VPP uses a main heap as a central memory pool for FIB data structures +entry allocations. + +Efficient memory management is crucial for VPP's performance, and the +main heap plays a significant role in this. + +It can be configured using the following command: + +```{cfgcmd} set vpp settings resource-allocation memory main-heap-page-size \<size\> +``` + +Sets the main heap page size for VPP. + +```{cfgcmd} set vpp settings resource-allocation memory main-heap-size \<size\> +``` + +Sets the main heap size for VPP. +(vpp-config-dataplane-physmem)= + +## Physical Memory Configuration + +VPP uses physical memory for packet buffers and interface operations. +The `physmem` setting controls how much memory VPP can allocate for +these operations. + +```{cfgcmd} set vpp settings resource-allocation memory physmem-max-size \<size\> +``` + +Sets the maximum amount of physical memory VPP can use for packet +processing and interface buffers. + +**Default**: 16GB (usually sufficient for most deployments) + +You may need to modify the value for high-throughput environments with +many interfaces, large packet buffers, very high packet rates, or +memory-constrained systems where you need to limit VPP's memory usage. + +**Physmem independent of main heap size** — physmem is for packet +buffers, main heap is for routing tables. + +:::{seealso} +- {ref}`Hugepages in VyOS Configuration for VPP <vpp-config-hugepages>` +- {ref}`VPP Buffer Configuration <vpp-config-dataplane-buffers>` - for + controlling buffer allocation within physmem +::: + +### Common configurations + +```none +# Reduce for memory-constrained systems +set vpp settings physmem max-size 4G + +# Increase for high-throughput environments +set vpp settings physmem max-size 32G +``` + +## Stats Memory Configuration + +VPP uses a dedicated statistics memory segment to store runtime +counters and telemetry data. This segment is used by the VPP CLI and +monitoring tools to access performance and status information. + +The statistics segment is allocated from hugepage memory and can be +configured independently from the main heap and physmem settings. + +You can configure statistics memory using the following commands: + +```{cfgcmd} set vpp settings resource-allocation memory stats page-size \<size\> +``` + +Sets the hugepage page size used for the statistics memory segment. + +```{cfgcmd} set vpp settings resource-allocation memory stats size \<size\> +``` + +Sets the total size of the statistics memory segment. + +Increasing this value may be required in large deployments with many +interfaces or enabled features that generate a high number of counters. + +Statistics memory is used only for telemetry and monitoring. It does +not affect packet buffer allocation or routing table memory. + +## Troubleshooting + +Improper configuration of main heap size can lead to performance +degradation or even system instability. If VPP runs out of memory in the +main heap, it may crash or exhibit erratic behavior. Symptoms you may +observe include: + +- Increased latency or packet loss +- Crashes or restarts of VPP processes, especially during routing table + population (for example, BGP session establishment) +- Error messages related to memory allocation failures + +You need to tune the main heap size based on expected FIB entries. Pay +attention: the same amount of routes with a single next-hop and with +multiple next-hops will consume different amounts of memory. + +For physmem, insufficient allocation can lead to packet drops, interface +initialization failures, and overall degraded performance. Symptoms +include: + +- Packet drops or failures to allocate buffers +- Increased latency or jitter in packet processing +- Crashes or restarts of VPP processes under heavy load + +You need to tune the physmem settings based on expected traffic patterns +and interface usage. Monitor memory usage closely and adjust the +configuration as needed to ensure optimal performance. |
