Re: [PATCH] Atomic pgrename on Windows

Hi, On March 30, 2020 9:17:00 AM PDT, Tom Lane wrote: >So far as pg_stat_tmp is concerned, I think there is reasonable hope >that that problem is just going to go away in the near future. >I've not been paying attention to the shared-memory stats collector >thread so I'm not sure if that's anywhe

Re: [PATCH] Atomic pgrename on Windows

David Steele writes: > On 1/11/20 5:13 PM, Alexander Korotkov wrote: >> Regarding "pg_stat_tmp/global.stat", which is a problem in particular >> case, we may evade file renaming altogether. Instead, we may >> implement shared-memory counter for filename. So, instead of >> renaming, new reads wil

Re: [PATCH] Atomic pgrename on Windows

On 1/11/20 5:13 PM, Alexander Korotkov wrote: On Tue, Jan 7, 2020 at 11:04 PM Tom Lane wrote: "If the link named by the new argument exists and the file's link count becomes 0 when it is removed and no process has the file open, the space occupied by the file shall be freed and the file shall n

Re: [PATCH] Atomic pgrename on Windows

On Tue, Jan 7, 2020 at 11:04 PM Tom Lane wrote: > Alexander Korotkov writes: > > I'm not sure issue we faced is really about single platform. TBH, the > > assumptions we place to rename function is very strict. We assume > > rename works atomically on system crash. And we indirectly assume it

Re: [PATCH] Atomic pgrename on Windows

Alexander Korotkov writes: > I'm not sure issue we faced is really about single platform. TBH, the > assumptions we place to rename function is very strict. We assume > rename works atomically on system crash. And we indirectly assume it > can work concurrently as least with file readers. The

Re: [PATCH] Atomic pgrename on Windows

On Tue, Jan 7, 2020 at 9:40 PM Tom Lane wrote: > Alexander Korotkov writes: > > On Tue, Jan 7, 2020 at 7:16 PM Tomas Vondra > > wrote: > >> I don't have access to a Windows machine and my developer experience > >> with that platform is pretty much nil, but I think this patch makes > >> sense. It

Re: [PATCH] Atomic pgrename on Windows

Alexander Korotkov writes: > On Tue, Jan 7, 2020 at 7:16 PM Tomas Vondra > wrote: >> I don't have access to a Windows machine and my developer experience >> with that platform is pretty much nil, but I think this patch makes >> sense. It's not an ideal solution, but it's not clear such solution >

Re: [PATCH] Atomic pgrename on Windows

Hi! On Tue, Jan 7, 2020 at 7:16 PM Tomas Vondra wrote: > I don't have access to a Windows machine and my developer experience > with that platform is pretty much nil, but I think this patch makes > sense. It's not an ideal solution, but it's not clear such solution > exists, and an improvement is

Re: [PATCH] Atomic pgrename on Windows

On Tue, Aug 06, 2019 at 09:03:08PM +0300, Alexander Korotkov wrote: ... Unfortunately, it seems that none of such strategies would fit all the cases. Basically, we have two option for renaming a file. * MoveFileEx() – safest possible option, less likely loose files, but takes a lock on target

Re: [PATCH] Atomic pgrename on Windows

Hi! I'd like to resume the discussion on this subject. Sorry for so long delay. On Sat, Jan 20, 2018 at 6:13 PM Magnus Hagander wrote: > On Tue, Nov 28, 2017 at 2:47 AM, Michael Paquier > wrote: >> >> On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov >> wrote: >> > Attached patch atomic-pg

Re: [PATCH] Atomic pgrename on Windows

On Tue, Mar 6, 2018 at 5:11 PM, David Steele wrote: > On 3/6/18 9:06 AM, Alexander Korotkov wrote: > > > > On Tue, Mar 6, 2018 at 5:04 PM, David Steele > > wrote: > > > > On 1/20/18 10:13 AM, Magnus Hagander wrote: > > > > > > Unlinking it first seems dang

Re: [PATCH] Atomic pgrename on Windows

On 3/6/18 9:06 AM, Alexander Korotkov wrote: > > On Tue, Mar 6, 2018 at 5:04 PM, David Steele > wrote: > > On 1/20/18 10:13 AM, Magnus Hagander wrote: > > > > Unlinking it first seems dangerous, as pointed out by Andres. > > > > What about first tr

Re: Re: [PATCH] Atomic pgrename on Windows

Hi, David! On Tue, Mar 6, 2018 at 5:04 PM, David Steele wrote: > On 1/20/18 10:13 AM, Magnus Hagander wrote: > > > > On Tue, Nov 28, 2017 at 2:47 AM, Michael Paquier > > mailto:michael.paqu...@gmail.com>> wrote: > > > > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov > > mailto:a.kor

Re: Re: [PATCH] Atomic pgrename on Windows

Hi Alexander, On 1/20/18 10:13 AM, Magnus Hagander wrote: > > On Tue, Nov 28, 2017 at 2:47 AM, Michael Paquier > mailto:michael.paqu...@gmail.com>> wrote: > > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov > mailto:a.korot...@postgrespro.ru>> wrote: > > Attached patch atomic-pgr

Re: [PATCH] Atomic pgrename on Windows

On Tue, Nov 28, 2017 at 2:47 AM, Michael Paquier wrote: > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov > wrote: > > Attached patch atomic-pgrename-windows-1.patch fixes this problem. It > > appears to be possible to atomically replace file on Windows – > ReplaceFile() > > does that. Rep

Re: [PATCH] Atomic pgrename on Windows

Greetings Alexander, all, * Alexander Korotkov (a.korot...@postgrespro.ru) wrote: > Attached patch atomic-pgrename-windows-1.patch fixes this problem. It > appears to be possible to atomically replace file on Windows – > ReplaceFile() does that. ReplaceFiles() requires target file to exist, > th

Re: [PATCH] Atomic pgrename on Windows

On 2017-11-29 10:13:32 +0800, Craig Ringer wrote: > On 29 November 2017 at 00:16, Alexander Korotkov > wrote: > > > > > For now, ReplaceFile() function looks like best choice for renaming > > statfiles. But it doesn't look good for critical datafiles whose are also > > renamed using pgrename, be

Re: [PATCH] Atomic pgrename on Windows

On 29 November 2017 at 00:16, Alexander Korotkov wrote: > > For now, ReplaceFile() function looks like best choice for renaming > statfiles. But it doesn't look good for critical datafiles whose are also > renamed using pgrename, because system can crash between rename of > destination file and

Re: [PATCH] Atomic pgrename on Windows

On Tue, Nov 28, 2017 at 5:02 AM, Craig Ringer wrote: > On 27 November 2017 at 14:28, Alexander Korotkov < > a.korot...@postgrespro.ru> wrote: > >> It's assumed in PostgreSQL codebase that pgrename atomically replaces >> target file with source file even if target file is open and being read by >>

Re: [PATCH] Atomic pgrename on Windows

On Tue, Nov 28, 2017 at 5:52 PM, Alexander Korotkov < a.korot...@postgrespro.ru> wrote: > On Tue, Nov 28, 2017 at 3:59 AM, Andres Freund wrote: > >> On 2017-11-28 09:47:45 +0900, Michael Paquier wrote: >> > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov >> > wrote: >> > > Attached patch ato

Re: [PATCH] Atomic pgrename on Windows

On Tue, Nov 28, 2017 at 3:59 AM, Andres Freund wrote: > On 2017-11-28 09:47:45 +0900, Michael Paquier wrote: > > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov > > wrote: > > > Attached patch atomic-pgrename-windows-1.patch fixes this problem. It > > > appears to be possible to atomically

Re: [PATCH] Atomic pgrename on Windows

On 27 November 2017 at 14:28, Alexander Korotkov wrote: > Hi! > > It's assumed in PostgreSQL codebase that pgrename atomically replaces > target file with source file even if target file is open and being read by > another process. And this assumption is true on Linux, but it's false on > Window

Re: [PATCH] Atomic pgrename on Windows

On 2017-11-28 09:47:45 +0900, Michael Paquier wrote: > On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov > wrote: > > Attached patch atomic-pgrename-windows-1.patch fixes this problem. It > > appears to be possible to atomically replace file on Windows – ReplaceFile() > > does that. ReplaceFil

Re: [PATCH] Atomic pgrename on Windows

On Mon, Nov 27, 2017 at 3:28 PM, Alexander Korotkov wrote: > Attached patch atomic-pgrename-windows-1.patch fixes this problem. It > appears to be possible to atomically replace file on Windows – ReplaceFile() > does that. ReplaceFiles() requires target file to exist, this is why we > still need