On Mon, May 06, 2024 at 05:15:55PM +0200, Brian Baboch wrote:
Hello,
We discovered that the CONFIG_INFINIBAND_IRDMA configuration option in the linux kernel is causing excessive memory usage on idle mode on specific servers like the DELL VEP4600 (https://www.dell.com/en-us/shop/ipovw/virtual-edge-platform-4600.
By default we were using Debian's linux-image-6.1.0-13-amd64 which is the stable 6.1.55-1 amd64, we then compiled the kernel again with the same config file from the stable 6.1.55 tag and had the same problem. We were able to resolve the memory problem by removing the `CONFIG_INFINIBAND_IRDMA` option from the kernel config.
The tag used to reproduce the problem is v6.1.55. adding the following config `CONFIG_INFINIBAND_IRDMA=m` causes the excessive memory usage to go from 1.4Gb to 7Gb.
Hi Brian,
Why do you think that this is a bug? DELL VEP4600 supports RDMA, so by enabling CONFIG_INFINIBAND_IRDMA, you compiled RDMA support for Intel NIC. https://dl.dell.com/topicspdf/vep4600_tech_guide_en-us.pdf
You can unload irdma.ko module and restore memory footprint.
Thanks