EDIT: Jveux bien mais si je passe sous spigot,tout les plugins que j'ai c'est garanti qu'ils vont marcher encore ou pas ? J'en ai déjà beaucoup de configuré comme groupmanager etc et jveux pas qu'ils marchent plus
Oui ils marcheront encore ^^
J'ai trouvé ça pour expliquer les différences Bukkit/Spigot.
Bukkit
Bukkit is great if you "just need it to work." There's not as many configuration options in Bukkit so it's more friendly towards the new server admin, it's also less likely to go wrong in the hands of someone who probably shouldn't be a server admin.
Bukkit is of course what Spigot is based on, and Bukkit therefore dictates the main direction that Spigot heads in. That's not a bad thing, because every ship needs a direction.
If you are looking to set up a server at home, or you are new to being a server admin, stick with Bukkit until you are comfortable with every setting in bukkit.yml and server.properties including the ones not set by default!
Spigot
Spigot is great if you need to tweak things for gameplay and/or performance. Spigot really excels at improving CPU and RAM usage compared to ordinary Bukkit, and I have seen RAM savings of 100%, where machines have gone from using 650MB to 325MB. CPU is not too different either, and on some systems I have seen spikes that caused 60% use drop to 20%.
Spigot adds a multitude of options to server.properties, including built-in, configurable, per-world Orebfusticator for Anti X-Ray and the ability to control growth rates of crops, as well as rainstorms frequencies and strengths. All of these things (and more) matter to a dedicated server, especially with multiple worlds.
Spigot is not for someone new to being a server admin, and there's probably no point in using it for a home server. Spigot is finely tuned for dedicated servers and it does that job very well.
Why does it matter?
RAM! RAM! RAM! On average, every player on a system uses between 50-100 MB of RAM (depending on the server's view distance settings as well as other factors). With the right modifications this can be lowered to around 40MB-80MB, but on a tin can system you can expect 100MB+ per person!
If you're looking to run a dedicated (i.e. permanent, not weekend or "until I get bored") server, RAM is important. It costs money. Without enough, your players suffer; too much, your money is wasted. Spigot gives you greater control over how you deal with these issues, but you have to know what you are doing to make the most of it.
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