When it comes to the Lok Sabha elections, the Congress and the BJP remain the only real contenders

Finance minister P Chidambaram's interim budget was along the expected lines for the market. The minister contained the fiscal deficit below the target and current account deficit also came in as per the estimates. The growth figure for the current f...

Tripartite meet : Demands 3-tier Panchayati Raj system in hills, backward status for GTA area

The Calcutta High Court Monday admitted a petition filed by a woman lecturer alleging that she was sexually harassed in a meeting of the Teachers'' Council and later suspended.

Suman has since skipped party programmes, even when Mamata Banerjee met party MPs to finalise a blueprint to accelerate development work before the Lok Sabha elections.

Jalpaiguri : Man carrying the bomb on his bicycle had links with KLO, say police sources

New Delhi, Feb 27 (PTI) The country's telecom sector has seen sharp decline in foreign investor interest with FDI plummeting by 96 per cent to USD 70.46 million in April to November 2012 period, the Economic Survey today said.

An audit scrutiny by the Comptroller and Auditor General has indicted the J-K Government for neglecting the Agriculture and Allied sector...

Madhya Pradesh looks to procure more wheat than never before, draws in farmers with bonuses.

After tryst with industry, govt shifts focus with agriculture policy that CM Naveen will unveil soon

US President Donald Trump has formally kicked off his 2020 re-election campaign at a rally in Orlando, Florida.

US President Donald Trump has formally launched his 2020 re-election campaign at a rally in Orlando, Florida, and called on his supporters to deliver a metaphorical "earthquake" at the ballots against his Democratic Party rivals.

Alexander, Charles K., author

Xiao, Bao-Lin, author

Boxwell, Michael, author

Fry, Christopher, 1907-2005

Duetting as a collective behavior Logue, David M.; Krupp, Daniel B. Mated birds of many species vocalize together, producing duets. Duetting behavior occurs at two levels of organization: the individual level and the pair level. Individuals initiate vocalizations, answer their mates’ vocalizations, and control the structure and timing of their own vocalizations. Pairs produce duets that vary with respect to duration, temporal coordination, and phrase-type combinations, among other properties. To make sense of this hierarchical structure, organize duetting research, and identify new avenues of investigation, we advocate a “collective behavior” approach to the study of duets. We critically review key terminology in the duetting literature in light of this approach, and elucidate six insights that emerge from the collective behavior approach: (1) Individual-level behaviors describe pair-level behaviors, but the opposite is not true; (2) The level of organization informs how we test for the rules that govern behavior; (3) Functional hypotheses about duetting must distinguish individual from group characters; (4) Stimulus-response, cybernetics, and entrainment offer alternative hypotheses for the cognitive control of duetting behavior; (5) Avian duetting has the potential to be a model system for the ontogeny of vocal interaction; and (6) The collective behavior approach suggests new avenues of research. Ultimately, we argue that nearly every aspect of duetting research stands to benefit from adopting a collective behavior approach. This approach also has applications to other forms of interactive vocal communication in birds and primates, including humans. Sherpa Romeo green journal. Open access article. Creative Commons Attribution License (CC BY) applies.

My session driver of choice for CodeIgniter is database. A while ago, I noticed millions of rows in the corresponding database table. That means that garbage collector was not working. I checked config.php for sess_regenerate_destroy, but it was already set to false. It was really weird because the problem seemed to have come out of nowhere – not much ago things were working just fine.

After a short investigation, I found out this was and still is a common problem for those who had upgraded their CodeIgniter version from 2.x to 3.x. Turns out, the later possesses heavy changes for Sessions library. And most importantly – fundamental changes in dealing with garbage: CodeIgniter 3.x relies on PHP's native grabage collector. So, in order to get things working again, we need to configure PHP properly.

The Solution

Today there are three PHP-native settings for dealing with session garbage collector. CodeIgniter's Session library has already taken care of one of them – gc_maxlifetime – so there's no need for an extra touch here. The problem lies within the rest: session.gc_probability and/or session.gc_divisor. These two determine when the garbage collector is running. Here's what php.net says:

session.gc_divisor coupled with session.gc_probability defines the probability that the gc (garbage collection) process is started on every session initialization. The probability is calculated by using gc_probability/gc_divisor, e.g. 1/100 means there is a 1% chance that the GC process starts on each request.

In my case, using ini_get() revealed the following values: 0 and 1000. The equation 0/1000=0 meant there was no chance the garbage collector would even run.

Finally, I solved the problem by using the values officially stated as default and by putting the following lines of PHP code into config/config.php file:

ini_set( 'session.gc_probability',	1 );
ini_set( 'session.gc_divisor',		100 );

Theoretically, this means that the garbage collector usually runs once every 100th request. It's more than enough, but it is up to you whether that causes too many unnecessary hits to database. An alternative solution for heavy-traffic websites could be having a 0% probability on the production site and a Cronjob-based script which removes database rows of the expired sessions.

Hayden Library - TA418.9.N35 S54 2011

Hayden Library - T174.7.C459 2011

Hayden Library - TP248.25.N35 Y68 2013

Hayden Library - QC176.8.N35 I575 2011

Hayden Library - TA418.9.N35 N357 2012

Hayden Library - TK7874.85.S474 2012

Hayden Library - T174.7.C456 2013

Hayden Library - T174.7.C46 2013

Hayden Library - T174.7.C459 2012

Online Resource

Hayden Library - T174.7.M523 2015

Barker Library - T174.7.A38 2015

Online Resource

London : Academic Press, 2020.

[Ottawa] : Statistics Canada = Statistique Canada, 2020

[Ottawa] : Statistics Canada = Statistique Canada, 2020

[Ottawa] : Statistics Canada = Statistique Canada, 2020