Re:Re:Re: My opinions on nocache and nocache_hack. :-)

Thanks, Henrik pal!

I take some time to look at the related mail and source files.
Here is the email you post me before,

no_cache == when the HTTP request indicates we should/must bypass the
cache.

nocache_hack == when squid.conf is configured to circument the
no_cache HTTP criteria..

since nocache_hack is to circumvent the no_cache criteria, and no_cache
criteria is to ask the cache to bypass the cache. Then I think you mean
no_cache means even though no_cache flag is assigned, if nocache_hack is
assigned at the same time, then we should violate the no_cache criteria.
So, we should ask the object to be cached in proxy in this case.
Am I correct?

But why you say the following?

No, they are not the same. Both indicates the user has
                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~
requested the object must not be from the cache, but in case
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
of nocache_hack there is squid.conf rules which may override
the request.

no_cache means "the user has requested the object must not
be from the cache". And nocache_hack means circument the
no_cache criteria, as you mentioned. They should on the
contrary, IMHO. Why you say they both indicate the same thing?

Best regards,
George Ma

----- Original Message -----
From: Henrik Nordstrom
To: maer727@sohu.com
Cc: squid-dev@squid-cache.org
Subject: Re:Re: My opinions on nocache and nocache_hack. :-)
Sent: Sun Apr 28 20:09:44 CST 2002

> The major use of nocache_hack is in refresh.c. There it makes a
> significant difference.
>
>
> On Sunday 28 April 2002 11:39, maer727@sohu.com wrote:
> > Thanks, Henrik pal!
> >
> > I have read the codes,
> > if (no_cache) {
> > #if HTTP_VIOLATIONS
> > if (Config.onoff.reload_into_ims)
> > request->flags.nocache_hack = 1;
> > else if (refresh_nocache_hack)
> > request->flags.nocache_hack = 1;
> > else
> > #endif
> > request->flags.nocache = 1;
> > }
> >
> > I think it means that in this case nocache and nocache_hack are not
> > the same. For example, in this case, nocache==true but
> > Config.onoff.reload_into_ims==false, nocache and nocache_hack are
> > not the same. Am I correct?
> >
> > In the pase time, I only notice the following two cases, so in my
> > mind they are the same all the time. :-) Now I think I have known
> > in some cases they are not always the same.
> >
> >
> > if (r->flags.nocache)
> > ipcacheInvalidate(r->host);
> > #if HTTP_VIOLATIONS
> > else if (r->flags.nocache_hack)
> > ipcacheInvalidate(r->host);
> > ......
> > if (r->flags.nocache || r->flags.nocache_hack) {
> >
> > Best regards,
> > George Ma
> >
> > ----- Original Message -----
> > From: Henrik Nordstrom
> > To: maer727@sohu.com
> > Cc: squid-dev@squid-cache.org
> > Subject: Re: My opinions on nocache and nocache_hack. :-)
> > Sent: Sun Apr 28 16:43:13 CST 2002
> >
> > > http://www.squid-cache.org/mail-archive/squid-dev/200204/0707.htm
> > >l
> > >
> > > On Sunday 28 April 2002 05:36, maer727@sohu.com wrote:
> > > > Thanks, Henrik pal!
> > > >
> > > > I search "no_cache" in squid.conf and do not find any rules.
> > > > What are the rules you mentioned?
> > > >
> > > > Another question, what means "may override the request"? Do you
> > > > mean in some cases even though the request asks the cache to
> > > > remove the object from cache, the object will still be kept in
> > > > cache without removing(so, it is on the contrary of the
> > > > request)?
> > > >
> > > > Best regards,
> > > > George Ma
> > > >
> > > > ----- Original Message -----
> > > > From: Henrik Nordstrom
> > > > To: maer727@sohu.com
> > > > Cc: squid-dev@squid-cache.org
> > > > Subject: Re:Re: My opinions on nocache and nocache_hack. :-)
> > > > Sent: Sat Apr 27 22:00:36 CST 2002
> > > >
> > > > > No, they are not the same. Both indicates the user has
> > > > > requested the object must not be from the cache, but in case
> > > > > of nocache_hack there is squid.conf rules which may override
> > > > > the request.
> > > > >
> > > > > On Saturday 27 April 2002 14:20, maer727@sohu.com wrote:
> > > > > > Thanks, Henrik pal!
> > > > > >
> > > > > > I think nocache_hack means the cache should not cache the
> > > > > > object. I mean the meaning of no_cache and nocache_hack are
> > > > > > the same.
> > > > > >
> > > > > > Am I correct?
> > > > > >
> > > > > > Best regards,
> > > > > > George Ma
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > From: Henrik Nordstrom
> > > > > > To: maer727@sohu.com
> > > > > > Cc: squid-dev@squid-cache.org
> > > > > > Subject: Re: My opinions on nocache and nocache_hack. :-)
> > > > > > Sent: Sat Apr 27 15:43:25 CST 2002
> > > > > >
> > > > > > > maer727@sohu.com wrote:
> > > > > > > > Hi, pals!
> > > > > > > >
> > > > > > > > After reading severals of source codes, I think
> > > > > > > > nocache_hack is the same as nocache if HTTP_VIOLATIONS
> > > > > > > > is defined. I have met with serveral cases where we
......
Received on Sun Apr 28 2002 - 08:49:39 MDT