JavaScript juża garbage collection awtomatika. Il-collector juża algoritmu mark-and-sweep: jibda mill-roots (l-oggett globali, il-current call stack), jissegna kollox reachable, imbagħad jitlibera kollox unreachable. Qatt m'għandek bżonn tiddaħħal free() manwalment — imma tista' aċċidentalment żżomm references ħajjin, u dan isabbab leaks.
// 1. Unbounded globals / caches that never shrink
window.cache = window.cache || {};
window.cache[id] = bigObject; // grows forever
// 2. Forgotten event listeners
el.addEventListener("click", handler);
// must call el.removeEventListener("click", handler) when done
// 3. Forgotten timers
const id = setInterval(tick, 1000);
// must clearInterval(id)
// 4. Closures capturing large objects longer than needed
function outer() {
const huge = new Array(1e6);
return () => huge.length; // keeps `huge` alive as long as the closure lives
}
Riferenzi minn kwalunkwe post li jirriżulta reachable (globali, listener ħaj, closure, DOM node distakkat li jmiss referenced f'JS) żżomm oggett milli jkun ikkollettat.
performance.memory; // rough heap size (Chrome)
// Chrome DevTools → Memory → take heap snapshots at two points and compare
Itlaq heap snapshots qabel/wara azzjoni; "retained size" li tikber steddina rivela x'inhu li ma jkunx ikkollettat.
const meta = new WeakMap(); // keys are weakly held — GC can collect them
meta.set(domNode, data); // doesn't prevent domNode from being garbage-collected
Applikazzjonijiet li jduru għal żmien twil (SPAs, Node servers) ikollhom crash jew jbaxtu minn leaks.
Il-fixes huma cleanup disċiplinata — neħħi listeners/timers, bounded caches (LRU), evita references li jdumu, u uża WeakMap/WeakSet għal metadata li m'għandux iżżomm oggetti ħajjin.