Can you add a name_prefix method to 0.2 runtime ’s builder?

[biluohc]

https://docs.rs/tokio/0.2.2/tokio/runtime/struct.Builder.html#method.thread_name

https://docs.rs/tokio/0.1.21/tokio/runtime/struct.Builder.html#method.name_prefix

Why is the name_prefix of 0.1 replaced by the thread_name of 0.2?
I need different thread names to help track task running，incremental id of 0.1 is good.

[biluohc]

Or store a closure as a thread name producer?

[biluohc]

@hawkw
Eliza Weisman: Hi @biluohc, I believe that if you pass a string to thread_name, it is still the prefix, as in 0.1.

Thandks for your repl, but looks no effect(Ubuntu 16.04, 1.39 stable, master branch tokio).

    let mut rt = tokio::runtime::Builder::new()
        .num_threads(3)
        .threaded_scheduler()
        .thread_name("tok-")
        .enable_all()
        .build()
        .unwrap();

top - 15:03:08 up 133 days,  3:07,  4 users,  load average: 0.38, 0.37, 0.46
Threads:   5 total,   0 running,   5 sleeping,   0 stopped,   0 zombie
%Cpu(s):  3.9 us,  2.7 sy,  0.0 ni, 91.4 id,  1.9 wa,  0.0 hi,  0.1 si,  0.0 st
KiB Mem : 32946936 total,   331500 free, 15747280 used, 16868156 buff/cache
KiB Swap:        0 total,        0 free,        0 used. 16646908 avail Mem

  PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND
13036 xxx      20   0  295.5m  14.0m   2.2m S  0.0  0.0   0:00.99 toks-threaded2
13039 xxx      20   0  295.5m  14.0m   2.2m S  0.0  0.0   0:00.00 log
13040 xxx      20   0  295.5m  14.0m   2.2m S  0.0  0.0   0:20.78 tok-
13041 xxx     20   0  295.5m  14.0m   2.2m S  0.0  0.0   0:20.83 tok-
13042 xxx      20   0  295.5m  14.0m   2.2m S  0.0  0.0   0:20.84 tok-

I only found it about thread::Builder::name from tokio(Master branch):

src/runtime/blocking/pool.rs
5:use crate::runtime::{self, io, time, Builder, Callback};
99:        builder: &Builder,
239:        let mut builder = thread::Builder::new().name(self.inner.thread_name.clone());

[carllerche]

An Fn to name threads is ok but it would need to be Send + Sync + ‘static

[biluohc]

Of course it should be Send + Sync + ‘static.

But if to implement it, should add an api (maybe thread_name_generator?) or just modify the existing method directly(thread_name)?

[carllerche]

Maybe just thread_name_fn? dunno, i'm open to suggestions :)