Re: Fix typos and inconsistencies for HEAD (take 7)
Hello Tom, 22.07.2019 7:14, Tom Lane wrote: >> Fixing both places sounds adapted to me. An alternative we could use >> here is just to say something like that: >> The effective resolution is only 1/HZ, which can be configured with >> kernel parameter (see man 7 time), and is 4 milliseconds by >> default. > Whatever we say here is going to be a lie on some platforms. > > Probably best just to say that the sleep resolution is platform-dependent > and leave it at that. I think, we can say "on many systems"/ "on most Unixen", and it would not be a lie. In my opinion, while a generic reference to platform-dependency is OK for developer' documentation, it makes the following passage in config.sgml vague (we don't give user a hint, what "the effective resolution" can be - several seconds/milliseconds/nanoseconds?): /The default value is 200 milliseconds (200ms). Note that on many systems, the// //effective resolution of sleep delays is 10 milliseconds; setting// //bgwriter_delay to a value that is not a multiple of 10// //might have the same results as setting it to the next higher multiple of 10. / -> /The default value is 200 milliseconds (200ms). Note that the// //effective resolution of sleep delays is paltform-dependent. setting// //bgwriter_delay to a value that is not a multiple of the effective resolution,/ /might have the same results as setting it to the next higher multiple./ Best regards, Alexander
Re: Fix typos and inconsistencies for HEAD (take 7)
Hello Michael, 22.07.2019 4:05, Michael Paquier wrote: >> Also, I found e-mail headers in optimizer/plan/README not relevant, so I >> propose to remove them. > Not sure about that part. I agree that the proposed fix is not complete, but just raises the demand for a subsequent fix. If you don't mind, I would return to such questionable and aside items after finishing with the unicums en masse. Best regards. Alexander
Re: Fix typos and inconsistencies for HEAD (take 7)
Michael Paquier writes: > On Sun, Jul 21, 2019 at 08:28:53AM +0300, Alexander Lakhin wrote: >> And another finding is related to the sleep effective resolution. `man 7 >> time` says "Since kernel 2.6.13, the HZ value is a kernel configuration >> parameter and can be 100, 250 (the default) ...", so the 10 >> milliseconds is not the most common effective resolution nowadays. >> I propose the corresponding patch for pgsleep.c, but we have a similar >> statement in doc/.../config.sgml. I think It should be fixed too. > Fixing both places sounds adapted to me. An alternative we could use > here is just to say something like that: > The effective resolution is only 1/HZ, which can be configured with > kernel parameter (see man 7 time), and is 4 milliseconds by > default. Whatever we say here is going to be a lie on some platforms. Probably best just to say that the sleep resolution is platform-dependent and leave it at that. regards, tom lane
Re: Fix typos and inconsistencies for HEAD (take 7)
On Sun, Jul 21, 2019 at 08:28:53AM +0300, Alexander Lakhin wrote: > Please consider fixing the next pack of typos and inconsistencies in the > tree: Thanks, all those things look fine. I have noticed one mistake. > 7.44. json_plperl -> jsonb_plperlu The path was incorrect here. > Also, I found e-mail headers in optimizer/plan/README not relevant, so I > propose to remove them. Not sure about that part. > And another finding is related to the sleep effective resolution. `man 7 > time` says "Since kernel 2.6.13, the HZ value is a kernel configuration > parameter and can be 100, 250 (the default) ...", so the 10 > milliseconds is not the most common effective resolution nowadays. > I propose the corresponding patch for pgsleep.c, but we have a similar > statement in doc/.../config.sgml. I think It should be fixed too. Fixing both places sounds adapted to me. An alternative we could use here is just to say something like that: The effective resolution is only 1/HZ, which can be configured with kernel parameter (see man 7 time), and is 4 milliseconds by default. -- Michael signature.asc Description: PGP signature
Re: Fix typos and inconsistencies for HEAD (take 7)
Alexander Lakhin writes: > Also, I found e-mail headers in optimizer/plan/README not relevant, so I > propose to remove them. FWIW, I think they're highly relevant, because they put a date on that text. I've not gone through that README lately, but I wouldn't be surprised if it's largely obsolete --- it hasn't been maintained in any meaningful way since Vadim wrote it. Without the headers, a reader would have no warning of that. What really ought to happen, likely, is for somebody to extract whatever is still useful there into a new(?) section in the parent directory's README. regards, tom lane
