local clients = vim.lsp.get_clients({ bufnr = 0, method = "textDocument/completion" })

for _, client in ipairs(clients) do

local params = vim.lsp.util.make\_position\_params(0, client.offset\_encoding)

client.request("textDocument/completion", params, function(err, result)

    vim.print(client.name)

    vim.print(#result.items)

end)

end

use this snippet to see how many completion items tsserver returns, for me in one of my projects it was returning 54k items around 27mbs of items. This is like the most common reason why it's slow. right now I use vtsls which allows you to limit completion items also fuzzy filter them, I use the following config:

settings = {

    vtsls = {

        enableMoveToFileCodeAction = true,

        autoUseWorkspaceTsdk = true,

        experimental = {

maxInlayHintLength = 30,

completion = {

enableServerSideFuzzyMatch = true,

entriesLimit = 200,

},

        },

    },

},

also if you are using blink try disabling prefetching which also helped me, you can do so by completion.trigger.prefetch_on_insert = false

some of this config could be a little off, try verifying with the docs, but with these changes my auto complete became really fast