A cache almost always uses a RW mutex or a lock free technique like copy on write/CAS to avoid contention.
A simple mutex is fine for less performance critical code with guaranteed exclusive/sequential access needs. Many transaction modes are implemented with a simple lock/mutex. > On Dec 20, 2020, at 6:59 AM, 'Axel Wagner' via golang-nuts > <golang-nuts@googlegroups.com> wrote: > > > Unless I specifically know that a variable will be written rarely and read > often, I tend to use `Mutex`. I'm too worried that the preferential treatment > of write-locks in an `RWMutex` leads to surprising contention-issues if there > isn't an overwhelming relationship between their frequencies. I also assume - > given that it has the more complicated semantics - that a `Mutex` is > generally cheaper than an `RWMutex`, all things being equal. > > So I tend to handle it the exact opposite of what you suggest - unless I have > a specific reason to use `RWMutex`, I default to `Mutex`. > >> On Sun, Dec 20, 2020 at 9:44 AM 김용빈 <kyb...@gmail.com> wrote: >> we usually both read and write for a value. not only read, nor write. >> >> with that, I feel RWMutex is always right choice. >> >> when should I use Mutex instead of RWMutex? >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/f597de36-b296-4f59-b756-adb1248387f5n%40googlegroups.com. > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/CAEkBMfEvPFgq-cQ41Bi%3D4OtaNait-k-2iXG3yWTb8Yj%2BjHDM3Q%40mail.gmail.com. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/2A9FF454-BD0C-4594-B3E9-FD1364077689%40ix.netcom.com.
