space bar lag in Nvim & Jdtls

Question

I've been working on a springboot project and wanted to use jdtls but I had lag whenever I hit the space bar it became annoying I tried reducing my plugins to the point where I only have my lsp installed but it didn't work.

the problem only applies to the space bar everything else seems snappy

my lsp config

local lsp = require('lsp-zero')

lsp.preset('recommended')

lsp.ensure_installed({
    'tsserver',
    'eslint',
    'jdtls',
})

local cmp = require('cmp')
local cmp_select = {behavior = cmp.SelectBehavior.Select}
local cmp_mappings = lsp.defaults.cmp_mappings({
    ['<C-p>'] = cmp.mapping.select_prev_item(cmp_select),
    ['<C-n>'] = cmp.mapping.select_next_item(cmp_select),
    ['<C-y>'] = cmp.mapping.confirm({ select = true }),
    ['<C-Space>'] = cmp.mapping.complete(),
})

lsp.set_preferences({
    sign_icons = { }
})

lsp.on_attach(function(client, bufnr)
    local opts = {buffer = bufnr, remap = false}

    vim.keymap.set('n', 'gd', function() vim.lsp.buf.definition() end, opts)
    vim.keymap.set('n', '<leader>vf', function () vim.lsp.buf.implementation() end, opts)
    vim.keymap.set('n', 'K', function() vim.lsp.buf.hover() end, opts)
    vim.keymap.set('n', '<leader>vws', function() vim.lsp.buf.workspace_symbol() end, opts)
    vim.keymap.set('n', 'gz', function() vim.diagnostic.open_float() end, opts)
    vim.keymap.set('n', '<d', function() vim.diagnostic.goto_next() end, opts)
    vim.keymap.set('n', '>d', function() vim.diagnostic.goto_prev() end, opts)
    vim.keymap.set('n', '<leader>vca', function() vim.lsp.buf.code_action() end, opts)
    vim.keymap.set('n', '<leader>vrr', function() vim.lsp.buf.references() end, opts)
    vim.keymap.set('n', '<leader>vrn', function() vim.lsp.buf.rename() end, opts)
    vim.keymap.set('i', '<leader>h', function() vim.lsp.buf.signature_help() end, opts)
end)

lsp.setup()

my java settings

local config = {
    cmd = {
        --
        "java", -- Or the absolute path '/path/to/java11_or_newer/bin/java'
        "-Declipse.application=org.eclipse.jdt.ls.core.id1",
        "-Dosgi.bundles.defaultStartLevel=4",
        "-Declipse.product=org.eclipse.jdt.ls.core.product",
        "-Dlog.protocol=true",
        "-Dlog.level=ALL",
        "-Xms1g",
        "--add-modules=ALL-SYSTEM",
        "--add-opens",
        "java.base/java.util=ALL-UNNAMED",
        "--add-opens",
        "java.base/java.lang=ALL-UNNAMED",
        --
        "-jar",
        "/path/to/jdtls_install_location/plugins/org.eclipse.equinox.launcher_VERSION_NUMBER.jar",
        "-configuration", "/path/to/jdtls_install_location/config_SYSTEM",
        "-data", "/Users/YOUR_MACHINE_NAME/local/share/nvim/java"
    },
    settings = {
        java = {
            signatureHelp = {enabled = true},
            import = {enabled = true},
            rename = {enabled = true}
        }
    },
    init_options = {
        bundles = {}
    }
}

Answer 1

finally found a fix to the issue

the culprit was a keymap in insert mode in my lsp config.

I found it using the command

verbose imap<space>

after removing the keybind the problem seems to go away