RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
Bug 1950282 - shutdown those unneeded network interfaces to save memory for kdump
Summary: shutdown those unneeded network interfaces to save memory for kdump
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 8
Classification: Red Hat
Component: kexec-tools
Version: 8.5
Hardware: Unspecified
OS: Unspecified
unspecified
low
Target Milestone: beta
: ---
Assignee: Coiby
QA Contact: xiaoying yan
URL:
Whiteboard:
Depends On:
Blocks: 2120188
TreeView+ depends on / blocked
 
Reported: 2021-04-16 10:09 UTC by Coiby
Modified: 2023-05-16 10:57 UTC (History)
2 users (show)

Fixed In Version: kexec-tools-2.0.25-3.el8
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
: 2120188 (view as bug list)
Environment:
Last Closed: 2023-05-16 09:02:40 UTC
Type: Bug
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2023:2953 0 None None None 2023-05-16 09:02:55 UTC

Description Coiby 2021-04-16 10:09:45 UTC
Description of problem:

Even with no carrier, a network interface is requested up, i.e., t IFF_UP flag is set. Thus netdev_ops->ndo_open is called to allocate the memory resources. For example, it's observed on ibm-p9b-19.ibm2.lab.eng.bos.redhat.com for the first kernel, i40e consumed ~15GB memory. If we shutdown those inactive network interfaces by "ip link set dev enP2p1s0fX down" would reduce the memory consumption from 16899MB to 5438MB,
```
[root@ibm-p9b-19 ~]# free -m
              total        used        free      shared  buff/cache   available
Mem:          63185       16899       44118          22        2167       45221
Swap:         32607           0       32607

[root@ibm-p9b-19 ~]# ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: enP2p1s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ac:1f:6b:56:e7:9c brd ff:ff:ff:ff:ff:ff
    inet 10.16.214.110/23 brd 10.16.215.255 scope global dynamic noprefixroute enP2p1s0f0
       valid_lft 70363sec preferred_lft 70363sec
    inet6 2620:52:0:10d6:ae1f:6bff:fe56:e79c/64 scope global dynamic noprefixroute 
       valid_lft 2591884sec preferred_lft 604684sec
    inet6 fe80::ae1f:6bff:fe56:e79c/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
3: enP2p1s0f1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9d brd ff:ff:ff:ff:ff:ff
4: enP2p1s0f2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9e brd ff:ff:ff:ff:ff:ff
5: enP2p1s0f3: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9f brd ff:ff:ff:ff:ff:ff
[root@ibm-p9b-19 ~]# ip link set dev enP2p1s0f1 down
[root@ibm-p9b-19 ~]# ip link set dev enP2p1s0f2 down
[root@ibm-p9b-19 ~]# ip link set dev enP2p1s0f3 down
[root@ibm-p9b-19 ~]# free -m
              total        used        free      shared  buff/cache   available
Mem:          63185        5438       55579          22        2167       56682
Swap:         32607           0       32607
[root@ibm-p9b-19 ~]# ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: enP2p1s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ac:1f:6b:56:e7:9c brd ff:ff:ff:ff:ff:ff
    inet 10.16.214.110/23 brd 10.16.215.255 scope global dynamic noprefixroute enP2p1s0f0
       valid_lft 70330sec preferred_lft 70330sec
    inet6 2620:52:0:10d6:ae1f:6bff:fe56:e79c/64 scope global dynamic noprefixroute 
       valid_lft 2591852sec preferred_lft 604652sec
    inet6 fe80::ae1f:6bff:fe56:e79c/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
3: enP2p1s0f1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9d brd ff:ff:ff:ff:ff:ff
4: enP2p1s0f2: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9e brd ff:ff:ff:ff:ff:ff
5: enP2p1s0f3: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether ac:1f:6b:56:e7:9f brd ff:ff:ff:ff:ff:ff
```

kexec-tools should shutdown those unneeded network interfaces to save memory. 

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.
2.
3.

Actual results:


Expected results:


Additional info:

Comment 7 errata-xmlrpc 2023-05-16 09:02:40 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (kexec-tools bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2023:2953


Note You need to log in before you can comment on or make changes to this bug.