It's just a config wrapper that passes "use less memory at the
expense of compression" parameters by default, so that we don't
accidentally construct resource-hungry (de)compressors.
Also includes a benchmark that measures the memory cost of the
small variants vs. the stock variants. The savings are significant
on both compressors (~8x less memory) and decompressors (~1.4x less,
not including the savings from the significantly smaller
window on the compression side - with those savings included it's
more like ~140x smaller).
BenchmarkSmallEncoder-8 56174 19354 ns/op 31 B/op 0 allocs/op
BenchmarkSmallEncoderWithBuild-8 2900 382940 ns/op 1746547 B/op 36 allocs/op
BenchmarkStockEncoder-8 48921 25761 ns/op 286 B/op 0 allocs/op
BenchmarkStockEncoderWithBuild-8 426 2630241 ns/op 13843842 B/op 124 allocs/op
BenchmarkSmallDecoder-8 123814 9344 ns/op 0 B/op 0 allocs/op
BenchmarkSmallDecoderWithBuild-8 41547 27455 ns/op 27694 B/op 31 allocs/op
BenchmarkStockDecoder-8 129832 9417 ns/op 1 B/op 0 allocs/op
BenchmarkStockDecoderWithBuild-8 25561 51751 ns/op 39607 B/op 92 allocs/op
Signed-off-by: David Anderson <danderson@tailscale.com>
... it was crashing for some reason, running out of stack while
loading a DLL in goversion. I don't understand Windows (or the Go
runtime for Windows) enough to know why that'd be problematic in that
context.
In any case, don't call it, as tryFixLogStateLocation does nothing on
Windows anyway.
tryFixLogStateLocation should probably just call version.CmdName
itself if/when it needs to, after the GOOS check.
The compressed blobs we send back and forth are small and infrequent,
which doesn't justify the 8MB * GOMAXPROCS memory that was being
allocated. This was the overwhelming majority of memory use in
tailscaled. On my system it goes from ~100M RSS to ~15M RSS (which is
still suspiciously high, but we can worry about that more later).
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
If a test calls log.Printf, 'go test' horrifyingly rearranges the
output to no longer be in chronological order, which makes debugging
virtually impossible. Let's stop that from happening by making
log.Printf panic if called from any module, no matter how deep, during
tests.
This required us to change the default error handler in at least one
http.Server, as well as plumbing a bunch of logf functions around,
especially in magicsock and wgengine, but also in logtail and backoff.
To add insult to injury, 'go test' also rearranges the output when a
parent test has multiple sub-tests (all the sub-test's t.Logf is always
printed after all the parent tests t.Logf), so we need to screw around
with a special Logf that can point at the "current" t (current_t.Logf)
in some places. Probably our entire way of using subtests is wrong,
since 'go test' would probably like to run them all in parallel if you
called t.Parallel(), but it definitely can't because the're all
manipulating the shared state created by the parent test. They should
probably all be separate toplevel tests instead, with common
setup/teardown logic. But that's a job for another time.
Signed-off-by: Avery Pennarun <apenwarr@tailscale.com>
This was the last of the three places that do TLS from clients (logs,
control, derp). With this, iOS should be able to use the
memory-efficient x509 root CertPool.
The autoselection should pick sensible paths for all of:
- Windows (LocalAppData)
- Mac (Library/Caches)
- Unix user (XDG_CACHE_DIR)
- Linux systemd service (CACHE_DIRECTORY)
As a last resort, if cache dir lookup fails, plops sufficiently
uniquely named files into the current working directory.
Signed-off-by: David Anderson <dave@natulte.net>
