table of contents
BPFTUNE(8) | System Manager's Manual | BPFTUNE(8) |
NAME¶
BPFTUNE - tool for auto-tuning of Linux kernel parameters via BPF
SYNOPSIS¶
OPTIONS := { { -V | --version } | { -h | --help } | { [-s | --stderr } | { [-c | --cgroup] cgroup} | { [-l | --libdir ] libdir} | [{ -d | --debug }] } { [-r | --learning_rate ] learning_rate} { [-R | --rollback ]} { [-S | --support ]} { [-p | --port ] port} { [-q | --query] query}
DESCRIPTION¶
bpftune requires CAP_BPF and CAP_TRACING capabilities, or CAP_SYS_ADMIN on older systemes. It is run via a systemd service, but can also be run standalone if required. To probe if your system supports the BPF features required for bpftune, run "bpftune -S". Basic bptune support requires BPF ring buffer, BPF hashmap and BPF sock ops and k[ret]probe support. On more modern systems, BPF tracing programs and BPF iterators are used. Individual tuners support legacy mode operation where possible. In order to support per-network-namespace tuning, netns cookie support is required; without that, only global tuning is supported.
OPTIONS¶
- -h, --help
- Show help information
- -V, --version
- Show version.
- -d, --debug
- Show debug output.
- -c, --cgroup
- Filter events for cgroup.
- -s, --stderr
- Log to standard error instead of syslog.
- -S, --support
- Scan system to see what level of bpftune support is present.
- -l, --libdir
- bptune extra plugin directory; defaults to /usr/local/lib64/bpftune . Both /usr/lib64/bpftune and /usr/local/lib64/bpftune can be used to install plugin tuners; if an alternative to /usr/local/lib64/bpftune is wanted, it must be specified via library path.
- -r, --learning_rate
1: tunables are changed by/within 3.125% of limit
2: tunables are changed by/within 6.25% of limit
3: tunables are changed by/within 12.5% of limit
4: tunables are changed by/within 25% of limit
So for example at rate 4, if we are within 25% of a limit, the limit is increased by 25%. Default learning rate is 4. Lower values are more conservative as they change only when closer to limits, but may require more frequent changes as a result.
- -p, --port
- TCP port to listen on for queries. If not specified, use an ephemeral localhost port.
- -q, --query
- Query bpftune. Supported queries include
help - show supported queries summary - show summary of changes made by tuners tuners - show loaded tuners and their state tunables - show supported tunables for loaded tuners