Golang: Processing 5 huge files concurrently

I have 5 huge (4 million rows each) logfiles that I process in Perl currently and I thought I may try to implement the same in Go and its concurrent features. So, being very inexperienced in Go, I was thinking of doing as below. Any comments on the approach will be greatly appreciated.
Some rough pseudocode:

var wg1 sync.WaitGroup
var wg2 sync.WaitGroup

func processRow (r Row) {
    wg2.Add(1)
    defer wg2.Done()
    res = <process r>
    return res
}

func processFile(f File) {
    wg1.Add(1)
    open(newfile File)
    defer wg1.Done()
    line = <row from f>
    result = go processRow(line)
    newFile.Println(result) // Write new processed line to newFile
    wg2.Wait()
    newFile.Close()

}

func main() {
    
    for each f logfile {
        go processFile(f)
    }
    wg1.Wait()
}

So, idea is that I process these 5 files concurrently and then all rows of each file will in turn also be processed concurrently.

Will that work?

You should definitely use channels to manage your processed rows. Alternatively you could also write another goroutine to handle your output.

var numGoWriters = 10
func processRow(r Row, ch chan<- string) {
res := process(r)
ch <- res
}
func writeRow(f File, ch <-chan string) {
w := bufio.NewWriter(f)
for s := range ch {
_, err := w.WriteString(s + "\n")
}
func processFile(f File) {
outFile, err := os.Create("/path/to/file.out")
if err != nil {
// handle it
}
defer outFile.Close()
var wg sync.WaitGroup
ch := make(chan string, 10)  // play with this number for performance
defer close(ch) // once we're done processing rows, we close the channel
// so our worker threads exit
fScanner := bufio.NewScanner(f)
for fScanner.Scan() {
wg.Add(1)
go func() {
processRow(fScanner.Text(), ch)
wg.Done()
}()
}
for i := 0; i < numGoWriters; i++ {
go writeRow(outFile, ch)
}
wg.Wait()  
}

Here we have processRow doing all the processing (I assumed to string), writeRow doing all the out I/O, and processFile tying each file together. Then all main has to do is hand off the files, spawn the goroutines, et voila.

func main() {
var wg sync.WaitGroup
filenames := [...]string{"here", "are", "some", "log", "paths"}
for fname := range filenames {
inFile, err := os.Open(fname)
if err != nil {
// handle it
}
defer inFile.Close()
wg.Add(1)
go processFile(inFile)
}
wg.Wait()