Re: [go-nuts] Should os.WriteFile call Sync()?

[Robert Engels]

Also, the real world edge case you are referring to is only (almost always) a hard system kernel crash - anything else and it will be written to disk. Also, even if it it written to disk you might still have a failure - which is can be mitigated with with redundant/raid storage.  Anyway, the option is there and anyone doing database or critical system design knows when and why to use it.  On Apr 17, 2025, at 9:18 AM, Robert Engels <reng...@ix.netcom.com> wrote:  Even if the OS writes it to disk there is the possibility of failure due to lazy writes by the drive itself. Which is why you need full fsync- which is coordinated all the way down. It is also many orders of magnitude slower. See this for performance difference details https://github.com/robaho/cpp_leveldb?tab=readme-ov-file#performance On Apr 16, 2025, at 6:09 PM, Karel Bílek <k...@karelbilek.com> wrote: I was quite surprised recently that, at least on linux, file.Close() does not guarantee file.Sync(); in some edge-cases, files can be not put properly to filesystem. If the data integrity is critical, it seems better to call file.Sync() before file.Close(). (Linux has this in close / fsync syscall manpages.) I am surprised that the docs don't mention this; also, that os.WriteFile does not call file sync, so even when os.WriteFile() returns no error, it doesn't mean the file is actually written on the disk! I have 2 questions 1) should this be documented in godoc somewhere? 2) should os.WriteFile explicitly call fsync? -- 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 visit https://groups.google.com/d/msgid/golang-nuts/dd574b31-8146-4710-9937-a56e8ecbe428n%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 visit https://groups.google.com/d/msgid/golang-nuts/019AC13F-8A75-4A8C-A9F9-B7A3DE9DA8D8%40ix.netcom.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 visit https://groups.google.com/d/msgid/golang-nuts/77C3B7D2-39A3-43BC-864D-E3561202040B%40ix.netcom.com.