mod | A Proxy Server for Go Modules | Proxy library

You will have to make your own tool for creating the WEBVTT file. And it's a simple process, you just need to get the information you need and fill it in the following format:

This package requires go v1.16, please upgrade your go version or use the appropriate docker builder.

Try adding:

I think it is already working actually, but you are in fact not catching the correct error. In your code you have:

OK, based on responses in IRC, this does not appear to be possible. One suggested workaround:

Looks like it may have been a precedence problem. This works:

Here is my attempt. A few things to note. I am not printing to CSV but just showing you the dataframes with the correct header information, you can handle the CSV output later.

You press enter after running the program to see the next tables with different headers.

The issue is that when connecting in a docker-compose network, you have to connect to the hostname of the container, in this case db.

You could also use the other container's IP but would take additional amount of work, it's simpler to just use the hostname.

In other words, you have the wrong connection string, I got this as well when connecting to localhost

You can see the cost of instructions on most mainstream architecture here and there. Based on that and assuming you use for example an Intel Skylake processor, you can see that one 32-bit imul instruction can be computed per cycle but with a latency of 3 cycles. In the optimized code, 2 lea instructions (which are very cheap) can be executed per cycle with a 1 cycle latency. The same thing apply for the sal instruction (2 per cycle and 1 cycle of latency).

This means that the optimized version can be executed with only 2 cycle of latency while the first one takes 3 cycle of latency (not taking into account load/store instructions that are the same). Moreover, the second version can be better pipelined since the two instructions can be executed for two different input data in parallel thanks to a superscalar out-of-order execution. Note that two loads can be executed in parallel too although only one store can be executed in parallel per cycle. This means that the execution is bounded by the throughput of store instructions. Overall, only 1 value can only computed per cycle. AFAIK, recent Intel Icelake processors can do two stores in parallel like new AMD Ryzen processors. The second one is expected to be as fast or possibly faster on the chosen use-case (Intel Skylake processors). It should be significantly faster on very recent x86-64 processors.

Note that the lea instruction is very fast because the multiply-add is done on a dedicated CPU unit (hard-wired shifters) and it only supports some specific constant for the multiplication (supported factors are 1, 2, 4 and 8, which mean that lea can be used to multiply an integer by the constants 2, 3, 4, 5, 8 and 9). This is why lea is faster than imul/mul.

I can reproduce the slower execution with -O2 using GCC 11.2 (on Linux with a i5-9600KF processor).

The main source of source of slowdown comes from the higher number of micro-operations (uops) to be executed in the -O2 version certainly combined with the saturation of some execution ports certainly due to a bad micro-operation scheduling.

Here is the assembly of the loop with -Os: