pgsql: Improve wording.
Log Message:
-----------
Improve wording.
Modified Files:
--------------
pgsql/doc/src/sgml:
runtime.sgml (r1.389 -> r1.390)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.389&r2=1.390)
On Mon, Dec 17, 2007 at 01:48:31PM +0000, Alvaro Herrera wrote:
Log Message:
-----------
Improve wording.Modified Files:
--------------
pgsql/doc/src/sgml:
runtime.sgml (r1.389 -> r1.390)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.389&r2=1.390)
I'm not sure what the leadup was to these wording changes in this
paragraph but it seems worse now. I object to the phrase: "to other
applications with careless memory allocation." This feature has
*nothing* to do with whether another application allocates memory
"carelessly" or not. If you meant "careless' as the oppisite to
"strict" then it needs to be reworded to say that.
It's also factually wrong, not just fork() can fail but any memory
allocation: sbrk(), mmap(), malloc(). The only case that is removed is
running out of memory on a page fault.
I'd suggest removing everything between the parentheses, or perhaps
something like: By tracking allocated memory rather than used memory
it removes the possibilty of failing in a page fault. This option also
require you allocate enoghh swap to cover all possible eventualities,
though in production it will not be used.
Have a nice day,
--
Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/
Show quoted text
Those who make peaceful revolution impossible will make violent revolution inevitable.
-- John F Kennedy
Martijn van Oosterhout wrote:
On Mon, Dec 17, 2007 at 01:48:31PM +0000, Alvaro Herrera wrote:
Log Message:
-----------
Improve wording.
I'd suggest removing everything between the parentheses, or perhaps
something like: By tracking allocated memory rather than used memory
it removes the possibilty of failing in a page fault. This option also
require you allocate enoghh swap to cover all possible eventualities,
though in production it will not be used.
I agree that the parenthised phrase should be removed.
http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.387&r2=1.391
I think your proposed wording is removed enough from what the
complainant was saying that it is not worth to stick it in. The point
here is, to what extent do we want to spoon-feed careless sysadmins?
--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.
On Tue, Dec 18, 2007 at 09:32:51AM -0300, Alvaro Herrera wrote:
Martijn van Oosterhout wrote:
On Mon, Dec 17, 2007 at 01:48:31PM +0000, Alvaro Herrera wrote:
Log Message:
-----------
Improve wording.I agree that the parenthised phrase should be removed.
http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.387&r2=1.391
That's fine with me. It's just that I figured that if we're going to
add something, we should at least add something factually accurate.
I think your proposed wording is removed enough from what the
complainant was saying that it is not worth to stick it in. The point
here is, to what extent do we want to spoon-feed careless sysadmins?
Not sure what the complaint was. The only useful advice I can think of
is that before turning it on you need to makes sure you have lots of
swap. For the rest, I think the wording was fine as it was.
Have a nice day,
--
Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/
Show quoted text
Those who make peaceful revolution impossible will make violent revolution inevitable.
-- John F Kennedy
Alvaro Herrera wrote:
Martijn van Oosterhout wrote:
On Mon, Dec 17, 2007 at 01:48:31PM +0000, Alvaro Herrera wrote:
Log Message:
-----------
Improve wording.I'd suggest removing everything between the parentheses, or perhaps
something like: By tracking allocated memory rather than used memory
it removes the possibilty of failing in a page fault. This option also
require you allocate enoghh swap to cover all possible eventualities,
though in production it will not be used.I agree that the parenthised phrase should be removed.
http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.387&r2=1.391
I think your proposed wording is removed enough from what the
complainant was saying that it is not worth to stick it in. The point
here is, to what extent do we want to spoon-feed careless sysadmins?
OK, I have removed the paratheses paragraph about fork() and added link
to an article about the OOM:
http://lwn.net/Articles/104179/
On Linux 2.6 and later, an additional measure is to modify the
kernel's behavior so that it will not <quote>overcommit</> memory.
Although this setting will not prevent the <ulink
url="http://lwn.net/Articles/104179/">OOM killer</> from being invoked
altogether, it will lower the chances significantly and will therefore
lead to more robust system behavior. This is done by selecting strict
overcommit mode via <command>sysctl</command>:
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +
Martijn van Oosterhout wrote:
-- Start of PGP signed section.
On Tue, Dec 18, 2007 at 09:32:51AM -0300, Alvaro Herrera wrote:
Martijn van Oosterhout wrote:
On Mon, Dec 17, 2007 at 01:48:31PM +0000, Alvaro Herrera wrote:
Log Message:
-----------
Improve wording.I agree that the parenthised phrase should be removed.
http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/runtime.sgml?r1=1.387&r2=1.391
That's fine with me. It's just that I figured that if we're going to
add something, we should at least add something factually accurate.I think your proposed wording is removed enough from what the
complainant was saying that it is not worth to stick it in. The point
here is, to what extent do we want to spoon-feed careless sysadmins?Not sure what the complaint was. The only useful advice I can think of
is that before turning it on you need to makes sure you have lots of
swap. For the rest, I think the wording was fine as it was.
We are back to the old wording, but a link to an OOM article was added:
http://lwn.net/Articles/104179/
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +
bruce wrote:
I think your proposed wording is removed enough from what the
complainant was saying that it is not worth to stick it in. The point
here is, to what extent do we want to spoon-feed careless sysadmins?OK, I have removed the paratheses paragraph about fork() and added link
to an article about the OOM:http://lwn.net/Articles/104179/
On Linux 2.6 and later, an additional measure is to modify the
kernel's behavior so that it will not <quote>overcommit</> memory.
Although this setting will not prevent the <ulink
url="http://lwn.net/Articles/104179/">OOM killer</> from being invoked
altogether, it will lower the chances significantly and will therefore
lead to more robust system behavior. This is done by selecting strict
overcommit mode via <command>sysctl</command>:
I just read that article in full and it does a better job of explaining
OOM than we ever could: :-)
Not everybody agrees that this (OOM) is a fruitful use of developer time.
Andries Brouwer came up with this analogy:
An aircraft company discovered that it was cheaper to fly its planes
with less fuel on board. The planes would be lighter and use less fuel
and money was saved. On rare occasions however the amount of fuel was
insufficient, and the plane would crash. This problem was solved by the
engineers of the company by the development of a special OOF
(out-of-fuel) mechanism. In emergency cases a passenger was selected and
thrown out of the plane. (When necessary, the procedure was repeated.) A
large body of theory was developed and many publications were devoted to
the problem of properly selecting the victim to be ejected. Should the
victim be chosen at random? Or should one choose the heaviest person? Or
the oldest? Should passengers pay in order not to be ejected, so that
the victim would be the poorest on board? And if for example the
heaviest person was chosen, should there be a special exception in case
that was the pilot? Should first class passengers be exempted? Now that
the OOF mechanism existed, it would be activated every now and then, and
eject passengers even when there was no fuel shortage. The engineers are
still studying precisely how this malfunction is caused.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +
Import Notes
Reply to msg id not found: | Resolved by subject fallback