# TO DO

* Have a good place for the cache directory.
* Expire entries in the cache.
* Possibly add my own anyhow "context", so when there's a permission issue, the user knows where to look.

# So Far...

* Fixes the GOROOT and GOPATH for files and directories with a+r only attributes.
* tar strips off the "go" directory within the archive.

# Go

Ok, it looks like GOROOT is managed by go.  See `go env`.
GOPATH seems like it needs to be managed still.

I've switched over to using `go env` for my information
(OS, ARCH, VERSION).  Which seems cleaner and clearer.

# Memory

Ok, memory usage is about 1.8MB peak heap usage. (Tokio & non-async), so
chunks and write_to work the same.

https://poby.medium.com/memory-profiling-using-valgrind-b30514f35117

`valgrind --log-file=memory1.log target/release/go-up update`

No leaks.  As if... ;)

## Viewing peak heap memory usage:

```
valgrind --tool=massif --stacks=yes --log-file=valgrind3.log target/release/go-up update
massif-visualizer massif.out.2496324 
```

## Valgrind memory usage

Logging total memory usage:
`cargo build --release; valgrind --log-file=memory1.log target/release/go-up update`

```
==2470578== HEAP SUMMARY:
==2470578==     in use at exit: 796,398 bytes in 5,858 blocks
==2470578==   total heap usage: 217,384 allocs, 211,526 frees, 269,243,726 bytes allocated
==2470578== 
```

I was concerned about the total bytes allocated, but that's not all at one time.

Example run:

```
thor@mount-olympus:~/Development/rust/reqwest/go-up$ cargo run -- update
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.07s
     Running `target/debug/go-up update`
Version: 1.24.2 [have 1.23.4]
Downloading newer version...
Clearing GOROOT /home/thor/go
Clearing GOPATH /home/thor/gopath
Extracting...
Extract cache/go1.24.2.linux-amd64.tar.gz to /home/thor/go
Updated 1.23.4 to 1.24.2
```