Possible unneccesary mysql write from Mage_Persistent module

[Flyingmana]

The event 'controller_front_send_response_after' is triggered on every page, and it seems always executing this observer https://github.com/OpenMage/magento-lts/blob/1.9.3.x/app/code/core/Mage/Persistent/Model/Observer/Session.php#L129 for logged in users.

Iam not sure about this area, actually Iam not sure what the persistent module is actually doing. But it seems it is looking for a change in the quote ID here, and I believe this change is not happening on the Category or Product page, which are both affected from this observer.

Also it saves it, even if it has not changed.

Is there anyone with more knowledge in this area who can give advice if this is something which can be improved?

[infabo]

The observer gets executed

Also it saves it, even if it has not changed.

My opinion: the persistent session (aka "persistent cart") has a defined lifetime (aka expiration time). note, the persistent session is only saved on logout. to ensure a most recent "updated_at" value of the session, it may be saved regardless of changes. This ensures, that the lifetime countdown start from logout - and not at a "last changed" time.

I would move

$sessionModel = Mage::helper('persistent/session')->getSession();

into the IF-block, where

$sessionModel->save();

is called.
This would at least save one database call (loading persistent session), when not at account/logout route.

[Flyingmana]

note, the persistent session is only saved on logout.

this is the problem I currently see: it is not only happening on logout, its happening on every request as soon as you are logged in.

The current logic says:
logged in == true => save
not logged in + currently use logout action => save

[infabo]

Hah, you're right. the linebreak confused me. ;)

The comment above the IF gives us a hint.

// Quote Id could be changed only by logged in customer

Reads like some dev liked to avoid the save for guests, but saving on logout.
But: I have no idea, when, where and why a guest would navigate to logout. 😆

[Flyingmana]

its probably more that the logout is the possible last action a "logged in" customer does, but the check would at this point in time already say "logged out"

[infabo]

IMHO it should read:

if (Mage::getSingleton('customer/session')->isLoggedIn() && ($request && $request->getActionName() == 'logout' && $request->getControllerName() == 'account')

Maybe I miss something. I assume the save is not needed on every request, but this throws another question: how to handle cookie-expiration (e.g. close browser or visitor inactivity) properly? This is what the persistence modules should take care of - and it will stop working, because only on logout the persistent session gets saved?

but the check would at this point in time already say "logged out"

Needs some xdebug session to verify.

[Flyingmana]

@infabo maybe check/debug which values the calls have during logout, may help to understand the if.

And yes, not saving it on every request, makes expiration a bit harder. I had hoped to at least find a few people who are actively using this feature and can better estimate what is needed.

[fballiano]

The only way to have the last updated timestamp of a quote is to update it at every request. Then you can make it expire in X hours, or, better, have a followup email for abandoned cart etc.