👀 Views: 52 💬 Answers: 1 📅 Created: 2025-06-16

go sorting performance Go

I'm building a feature where I'm working on a Go application where I need to sort a large slice of structs based on a specific field, but I'm experiencing significant performance issues... The slice contains over a million records, and I'm using the `sort.Slice` function with a custom comparator. However, the sorting seems to take an excessively long time, especially when the data contains many duplicates. Here's a simplified version of my struct and sorting logic: ```go package main import ( "fmt" "sort" ) type Record struct { ID int Name string Value float64 } func main() { records := make([]Record, 1000000) // Assume records are populated here // Sorting by Value field sort.Slice(records, func(i, j int) bool { return records[i].Value < records[j].Value }) } ``` While this approach works, I noticed that the sorting time increases dramatically when there are many records with the same `Value`. I ran a benchmark and found that sorting takes about 5 seconds when duplicates make up 70% of the array. I tried switching to a different sorting algorithm and manually implementing a quicksort, but that didn't yield any improvements. I also considered using the `sort.Stable` function, but I’m not sure how it applies in this case. Should I be using a different approach altogether, or is there a way to optimize my `sort.Slice` implementation? I’m using Go 1.20.3, and I would appreciate any insights or best practices regarding sorting large datasets with potential duplicates. Any ideas how to fix this?