Install the bpf program for all pods and collect/expose the data #13
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robertgzr
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Gopkg.lock
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why is this pkg mentioned here? it does not seem to be used anywhere (neither in cgnet or in the vendored pkgs), or vendored?
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AFAIU this file is generated by the package manager.
So to answer your question, one would have to look into the dep's behaviour.
Dockerfile
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Gopkg.lock
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any reason for using master instead of a released version?
bpf/controller.go
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bpf/controller.go
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Why using a callback in parameter 3 instead of just having the lookup function returning the value?
c.packetsHandle(lookup(c.module, packetsKey))
bpf/src/cgnet.c
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Could you use the same name for the section and the variable name?
something like:
struct bpf_map_def SEC("maps/count_map") count_map = {
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Please add a comment to document:
- what is the key: define the keys nearby the map definition, so it's clearer.
- what is the value: a counter
- how it is used to communicate: values initialized to zero by userspace and incremented by the ebpf program
Just before the map definition:
#define PACKETS_KEY 0
#define BYTES_KEY 1
In the count_packets function:
int packets_key = PACKETS_KEY, bytes_key = BYTES_KEY;
cmd/serve.go
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is it possible to get this from the Kubernetes API rather than assuming the path is built in a specific way?
/cc @asymmetric @nhlfr
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I think you could follow this and do something like client.Get().Namespace("foo").Resource("bar").URL().
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@asymmetric But that only gives me the resource URL I need the path to the pods cgroup here
@alban I looked though http://godoc.org/k8s.io/api/core/v1#Pod to find a way to get the cgroup for pods but building it ourselfs seems to be the only way. Maybe @nhlfr knows...
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If k8s does not provide it, you might have to ask Docker the leader pid of the container and then check in /proc/$pid/cgroup...
You could file an issue and add a // FIXME: ... if you want to do that later.
cmd/serve.go
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cleanup the bpf module? Or at least. add a // FIXME: ... to remember
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That was actually why I filed #7 because I didn't know if you had to do any cleanup work.
Will fix this now...
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This introduces a bpf controller that runs the lookup loop for every cgroup we attach a program to, reads the map and executes handlers that write the tracked data to Prometheus metrics. The top subcommand uses the same code but implements different handlers. Closes #4, closes #5, closes #6, closes #9
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|
Any more feedback here? |
| import ( | ||
| "bytes" | ||
| "fmt" | ||
| "log" |
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"log" doesn't seem to be used anywhere, so we get build error.
| func (c *Controller) Stop() { | ||
| c.quit <- struct{}{} | ||
| if err := c.module.Close(); err != nil { | ||
| Log.Error("error closing bpf.Module", "err", err) |
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Shouldn't it be log instead of Log?
And log needs to be imported, otherwise we get build errors.
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Ah that's left over from the logging I introduced but split out of this PR. thx will use the log pkg here
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This introduces a bpf controller that runs the lookup look for every cgroup we attach a program to and executes handlers that write the tracked data to Prometheus metrics that get exposed on port 9101. The top subcommand uses the same code but implements different handlers. It also improves overall logging and adds a flag to adjust the verbosity.
Closes #4, #5, #6, #9