Diary sync

content/diary.md

@@ -20,6 +20,7 @@ Specialized versions of methods for specific types are `MethodInstance`s, an int
 
 `Base.arrayref` in, e.g., `@code_typed` is from [boot.jl](https://github.com/JuliaLang/julia/blob/e8f89682d7b434f1159626a213756b3691f48d03/base/boot.jl#L962)
 
+{{< detail "Wait, `arrayref`?" >}}
 ```julia
 # for backward compat
 arrayref(inbounds::Bool, A::Array, i::Int...) = Main.Base.getindex(A, i...)
@@ -28,6 +29,7 @@ arrayref(inbounds::Bool, A::Array, i::Int...) = Main.Base.getindex(A, i...)
 > as of 1..11, `arrayref` is no longer a thing Julia knows about. `Array` is basically a first class `mutable struct` built on top of `Memory`. Initially we removed `arrayref` entirely, but it turns out that enough people were using it (mostly for dumb reasons) that we added a fallback to prevent code from breaking
 
 cf. 8
+{{< /detail >}}
 %%
 
 https://docs.julialang.org/en/v1/devdocs/boundscheck/#Propagating-inbounds TODO
@@ -46,10 +48,12 @@ In REPL, `using REPL; ModuleName <Alt+m>`: ["Set mod as the default contextual m
 %%
 
 If you want to add custom diff rules for [`ForwardDiff.jl`](https://github.com/JuliaDiff/ForwardDiff.jl), use [ForwardDiffChainRules.jl](https://github.com/ThummeTo/ForwardDiffChainRules.jl) to [add a ForwardDiff dispatch for an already existing frule](https://github.com/ThummeTo/ForwardDiffChainRules.jl/blob/decd2c40a2eea4a1ae6aea9852a35ee2f7a22575/README.md?plain=1#L28).
+{{< detail "Details" >}}
 Note that you can't add rules to `DiffRules` directly.
 The reason is `ForwardDiff` works by adding dispatches for the `DiffRules` rules; to do that, it reads the `DiffRules` tables containing all the rules. Doing, say, `DiffRules.@define_diffrule`, adds the rules *after* they've been read by `ForwardDiff`, so you get no dispatches for your custom rule.
 You can also do something to add an additional dispatch of your function for values of type `ForwardDiff.Dual`: `myfunction(::ForwardDiff.Dual)`.
 However, this is redundant and error-prone, while with `ForwardDiffChainRules` you can *re-use* the differentiation code defined in an existing `ChainRulesCore.frule` without having to re-code the diff rules
+{{< /detail >}}
 %%
 
 Increase `VSCode -> Settings (UI) -> Terminal > Integrated: Scrollback` for larger history buffer in REPL
@@ -67,4 +71,103 @@ Writing documentation [according to the field values of a type instance rather t
 Using [metaprogramming for docgen](https://docs.julialang.org/en/v1/manual/documentation/#Advanced-Usage)
 %%
 
+[`julia --help-hidden`](https://docs.julialang.org/en/v1/manual/command-line-interface/#command-line-interface)
+%%
+
+Use [`TimerOutputs.jl`](https://github.com/KristofferC/TimerOutputs.jl) for profiling
+{{< detail "Example usage" >}}
+```julia
+using TimerOutputs
+
+# Create a TimerOutput, this is the main type that keeps track of everything.
+const to = TimerOutput()
+
+# Time a section code with the label "sleep" to the `TimerOutput` named "to"
+@timeit to "sleep" sleep(0.02)
+
+# Create a function to later time
+rands() = rand(10^7)
+
+# Time the function, @timeit returns the value being evaluated, just like Base @time
+rand_vals = @timeit to "randoms" rands();
+
+# Nested sections (sections with same name are not accumulated
+# if they have different parents)
+function time_test()
+    @timeit to "nest 1" begin
+        sleep(0.1)
+        # 3 calls to the same label
+        @timeit to "level 2.1" sleep(0.03)
+        @timeit to "level 2.1" sleep(0.03)
+        @timeit to "level 2.1" sleep(0.03)
+        @timeit to "level 2.2" sleep(0.2)
+    end
+    @timeit to "nest 2" begin
+        @timeit to "level 2.1" sleep(0.3)
+        @timeit to "level 2.2" sleep(0.4)
+    end
+end
+
+time_test()
+
+# exception safe
+function i_will_throw()
+    @timeit to "throwing" begin
+        sleep(0.5)
+        throw(error("this is fine..."))
+        print("nope")
+    end
+end
+
+i_will_throw()
+
+# Use disable_timer! to selectively turn off a timer, enable_timer! turns it on again
+disable_timer!(to)
+@timeit to "not recorded" sleep(0.1)
+enable_timer!(to)
+
+# Use @notimeit to disable timer and re-enable it afterwards (if it was enabled
+# before)
+@notimeit to time_test()
+
+# Call to a previously used label accumulates data
+for i in 1:100
+    @timeit to "sleep" sleep(0.01)
+end
+
+# Can also annotate function definitions
+@timeit to funcdef(x) = x
+
+funcdef(2)
+
+# Or to instrument an existing function:
+foo(x) = x + 1
+timed_foo = to(foo)
+timed_foo(5)
+```
+
+```julia
+julia> show(to) # Print the timings in the default way
+────────────────────────────────────────────────────────────────────────
+                            Time                    Allocations
+                    ───────────────────────   ────────────────────────
+Tot / % measured:        94.9s /   3.1%            115MiB /  76.6%
+
+Section       ncalls     time    %tot     avg     alloc    %tot      avg
+────────────────────────────────────────────────────────────────────────
+sleep            101    1.22s   41.2%  12.1ms   12.6KiB    0.0%     128B
+nest 2             1    704ms   23.7%   704ms   1.69KiB    0.0%  1.69KiB
+level 2.2        1    402ms   13.5%   402ms      112B    0.0%     112B
+level 2.1        1    302ms   10.2%   302ms      112B    0.0%     112B
+throwing           1    503ms   16.9%   503ms      208B    0.0%     208B
+nest 1             1    399ms   13.5%   399ms   2.31KiB    0.0%  2.31KiB
+level 2.2        1    201ms    6.8%   201ms      112B    0.0%     112B
+level 2.1        3   96.3ms    3.2%  32.1ms      640B    0.0%     213B
+randoms            1    137ms    4.6%   137ms   88.1MiB  100.0%  88.1MiB
+foo                1    375ns    0.0%   375ns     0.00B    0.0%    0.00B
+funcdef            1    334ns    0.0%   334ns     0.00B    0.0%    0.00B
+────────────────────────────────────────────────────────────────────────
+```
+{{< /detail >}}
+%%
 {{< /diaryList >}}