Global Cooldown

Boethius

[top]Global Cooldown

The global cooldown is the time that must elapse between actions taken by the player. It was implemented to limit macroing and botting, but it also prevents low ping players from gaining an unfair advantage over high ping players by limiting the number of actions per minute that can be executed.

The base global cooldown for Druids in cat form and Rogues is 1.0 seconds. The base global cooldown for all other classes is 1.5 seconds.

[top]Lowering the Global Cooldown

As of 2.4, spell haste will lower the global cooldown when casting spells to a minimum of 1.0. The reduction amount is equal to the percentage of cast time reduced by spell haste, up to a maximum of 33% (requires 50% spell haste). The reduction scales smoothly, meaning your GCD can be any value between 1.0 and 1.5 depending on the amount of spell haste. 50% spell haste requires 788 spell haste rating.

[top]Non-GCD Abilities

Not all abilities are tied to the global cooldown, however all these abilities have some sort of separate timer that prevents them from being spammed indefinitely. It is worth noting that even non-GCD abilities can interfere with the 0.5 second hidden cast time on Autoshot. Some examples of abilities that do not incur the GCD when activated include:

Most clickable trinkets
Most pet abilities
On-next-swing abilities like Maul or Cleave
Warrior Stance Change, Shield Block, Taunt, Bloodrage, Spell Reflect
Paladin: Judgment, Divine Favor
Hunter: Kill Command
Mage: Presence of Mind, Arcane Power
Warlock: Fel Domination, Demonic Sacrifice
Shaman, Druid: Nature's Swiftness

[top]Macroing Non-GCD Abilities

Non-GCD abilities may be macroed together in sequence and in combination with a GCD-invoking action. Some examples:

Nature's Swiftness + Heal

/cast Nature's Swiftness
/cast Healing Wave

Trinket + PoM + AP + Pyro

/use 13
/cast Presence of Mind
/cast Arcane Power
/cast Pyroblast

Bearpot

/cancelform
/use Super Healing Potion
/cast Bear Form

[top]Changing Gear

Changing equipment (weapons, shields, etc) in combat triggers the GCD; it should however be noted that if you swap equipment while casting, no additional cooldown is incurred and the gear is immediately swapped. This is most commonly used by Mages, who begin casting Evocation then swap in a weapon with a high amount of Intellect to improve their regen. After Evocation finishes, the mage can then begin casting a spell then switch back to their normal weapon. By following this sequence, the GCD will not be incurred on either weapon swap.

[top]Bloodlust/Heroism

Bloodlust and Heroism will not lower the global cooldown for classes that do not benefit from spell haste. Classes that make use of spell haste receive the benefit of Bloodlust lowering their global cooldown as noted above. This can be proven using the following UI hook and spamming an instant spell with no cooldown inside and outside of Bloodlust/Heroism:

/run hooksecurefunc("CooldownFrame_SetTimer", function(_, start, duration, enable) if start > 0 and enable > 0 then DEFAULT_CHAT_FRAME:AddMessage(duration) end end)

Larisroth · 04/10/08, 9:22 PM

Could be worth including the information about how to detect the gcd and the very limited gcd protection that Feral Druids use.

/script local gcd=GetSpellCooldown("Dire Bear Form"); if gcd==0 then CancelPlayerBuff("Dire Bear Form") end;
/stopmacro [stance:1]

The first part will work for any spell (or action), but about the only things you can modify and detect later in a macro are stances that function as buffs. Not sure if that works with the hidden buffs that govern warrior stances or not though.

Would be nice if Blizzard added a [gcd] conditional.

ETA:
Also, the part about heroism and the gcd is a bit ambiguous. Does it reduce the gcd for classes that can cast spells? (as written), or does it reduce the gcd after spell casting?