9 Commits (1f95bfedf7b3454a0d88956413e00e6d55e0f616)

Author	SHA1	Message	Date
Mihai Parparita	97b6d3e917	sockstats: remove per-interface stats from Get ... They're not needed for the sockstats logger, and they're somewhat expensive to return (since they involve the creation of a map per label). We now have a separate GetInterfaces() method that returns them instead (which we can still use in the PeerAPI debug endpoint). If changing sockstatlog to sample at 10,000 Hz (instead of the default of 10Hz), the CPU usage would go up to 59% on a iPhone XS. Removing the per-interface stats drops it to 20% (a no-op implementation of Get that returns a fixed value is 16%). Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Will Norris	a1d9f65354	ipn,log: add logger for sockstat deltas ... Signed-off-by: Will Norris <will@tailscale.com> Co-authored-by: Melanie Warrick <warrick@tailscale.com>	2 years ago
Mihai Parparita	b64d78d58f	sockstats: refactor validation to be opt-in ... Followup to #7499 to make validation a separate function ( GetWithValidation vs. Get). This way callers that don't need it don't pay the cost of a syscall per active TCP socket. Also clears the conn on close, so that we don't double-count the stats. Also more consistently uses Go doc comments for the exported API of the sockstats package. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	ea81bffdeb	sockstats: export as client metrics ... Though not fine-grained enough to be useful for detailed analysis, we might as well export that we gather as client metrics too, since we have an upload/analysis pipeline for them. clientmetric.Metric.Add is an atomic add, so it's pretty cheap to also do per-packet. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	4c2f67a1d0	net/sockstat: fix per-interface statistics not always being available ... withSockStats may be called before setLinkMonitor, in which case we don't have a populated knownInterfaces map. Since we pre-populate the per-interface counters at creation time, we would end up with an empty map. To mitigate this, we do an on-demand request for the list of interfaces. This would most often happen with the logtail instrumentation, since we initialize it very early on. Updates tailscale/corp#9230 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	f4f8ed98d9	sockstats: add validation for TCP socket stats ... We can use the TCP_CONNECTION_INFO getsockopt() on Darwin to get OS-collected tx/rx bytes for TCP sockets. Since this API is not available for UDP sockets (or on Linux/Android), we can't rely on it for actual stats gathering. However, we can use it to validate the stats that we collect ourselves using read/write hooks, so that we can be more confident in them. We do need additional hooks from the Go standard library (added in tailscale/go#59) to be able to collect them. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	6ac6ddbb47	sockstats: switch label to enum ... Makes it cheaper/simpler to persist values, and encourages reuse of labels as opposed to generating an arbitrary number. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	3e71e0ef68	net/sockstats: remove explicit dependency on wgengine/monitor ... Followup to #7177 to avoid adding extra dependencies to the CLI. We instead declare an interface for the link monitor. Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago
Mihai Parparita	9cb332f0e2	sockstats: instrument networking code paths ... Uses the hooks added by tailscale/go#45 to instrument the reads and writes on the major code paths that do network I/O in the client. The convention is to use "<package>.<type>:<label>" as the annotation for the responsible code path. Enabled on iOS, macOS and Android only, since mobile platforms are the ones we're most interested in, and we are less sensitive to any throughput degradation due to the per-I/O callback overhead (macOS is also enabled for ease of testing during development). For now just exposed as counters on a /v0/sockstats PeerAPI endpoint. We also keep track of the current interface so that we can break out the stats by interface. Updates tailscale/corp#9230 Updates #3363 Signed-off-by: Mihai Parparita <mihai@tailscale.com>	2 years ago