Merge pull request #68 from joshuay03/update-readme

Add start/stop and options to README

README.md

@@ -8,10 +8,10 @@ Next-generation Ruby 3.2.1+ sampling profiler. Tracks multiple threads, GVL acti
 
 [Livestreamed demo: Pairin' with Aaron (YouTube)](https://www.youtube.com/watch?v=9nvX3OHykGQ#t=27m43)
 
-Sidekiq jobs from Mastodon (time, threded)
+Sidekiq jobs from Mastodon (time, threaded)
 : https://share.firefox.dev/44jZRf3
 
-Puma web requests from Mastodon (time, threded)
+Puma web requests from Mastodon (time, threaded)
 : https://share.firefox.dev/48FOTnF
 
 Rails benchmark - lobste.rs (time)
@@ -50,16 +50,34 @@ starting profiler with interval 500
 written to /tmp/profile20240328-82441-gkzffc.vernier.json
 ```
 
-### Block of code
+#### Block of code
 
 ``` ruby
-Vernier.run(out: "time_profile.json") do
+Vernier.profile(out: "time_profile.json") do
  some_slow_method
 end
 ```
 
+Alternatively you can use the aliases `Vernier.run` and `Vernier.trace`.
+
+#### Start and stop
+
+```ruby
+Vernier.start_profile(out: "time_profile.json")
+
+some_slow_method
+
+# some other file
+
+some_other_slow_method
+
+Vernier.stop_profile
+```
+
 ### Retained memory
 
+#### Block of code
+
 Record a flamegraph of all **retained** allocations from loading `irb`.
 
 ```
@@ -68,6 +86,14 @@ ruby -r vernier -e 'Vernier.trace_retained(out: "irb_profile.json") { require "i
 
 Retained-memory flamegraphs must be interpreted a little differently than a typical profiling flamegraph. In a retained-memory flamegraph, the x-axis represents a proportion of memory in bytes, _not time or samples_ The topmost boxes on the y-axis represent the retained objects, with their stacktrace below; their width represents the percentage of overall retained memory each object occupies.
 
+### Options
+
+Option | Description
+:- | :-
+`mode` | The sampling mode to use. One of `:wall`, `:retained` or `:custom`. Default is `:wall`.
+`out` | The file to write the profile to.
+`gc` | Initiate a full and immediate garbage collection cycle before profiling. Only available in `:retained` mode.
+
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.