Tried on windows.

Indeed, with previous settings in my init file, I do not see anymore emacs eating all memory, currently it remains at ~150Mo while idle.

The only trouble is that some packages fail to be natively compiled as "smart-mode-line" with the same error :

Debugger entered--Lisp error: (wrong-number-of-arguments (3 . 4) 2)

I blacklisted this package too.

Details of the error follows, I presume this is a compatibility problem with emacs 28.0.50 ?

Regards

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Compiling c:/Users/xxx/.emacs.d/elpa/smart-mode-line-20190527.1156/smart-mode-line.el...
Debugger entered--Lisp error: (wrong-number-of-arguments (3 . 4) 2)
  #f(compiled-function (obsolete-name current-name when &optional docstring) "Make OBSOLETE-NAME a variable alias for CURRENT-NAME and mark it obsolete.\n\nWHEN should be a string indicating when the variable was first\nmade obsolete, for example a date or a release number.\n\nThis macro evaluates all its parameters, and both OBSOLETE-NAME\nand CURRENT-NAME should be symbols, so a typical usage would look like:\n\n  (define-obsolete-variable-alias 'foo-thing 'bar-thing \"27.1\")\n\nThis macro uses `defvaralias' and `make-obsolete-variable' (which see).\nSee the Info node `(elisp)Variable Aliases' for more details.\n\nIf CURRENT-NAME is a defcustom or a defvar (more generally, any variable\nwhere OBSOLETE-NAME may be set, e.g. in an init file, before the\nalias is defined), then the define-obsolete-variable-alias\nstatement should be evaluated before the defcustom, if user\ncustomizations are to be respected.  The simplest way to achieve\nthis is to place the alias statement before the defcustom (this\nis not necessary for aliases that are autoloaded, or in files\ndumped with Emacs).  This is so that any user customizations are\napplied before the defcustom tries to initialize the\nvariable (this is due to the way `defvaralias' works).\n\nFor the benefit of Customize, if OBSOLETE-NAME has\nany of the following properties, they are copied to\nCURRENT-NAME, if it does not already have them:\n`saved-value', `saved-variable-comment'." #<bytecode 0x127e504c6e942a72>)('sml/time-format 'display-time-format)
  macroexpand((define-obsolete-variable-alias 'sml/time-format 'display-time-format) ((sml/-debug . #f(compiled-function (fmt &rest r) #<bytecode -0x528c1381ccb3bab>)) (declare-function . byte-compile-macroexpand-declare-function) (eval-when-compile . #f(compiled-function (&rest body) #<bytecode -0xcee878b9e5c479>)) (eval-and-compile . #f(compiled-function (&rest body) #<bytecode 0x31ea4933231cd9b>)) (with-suppressed-warnings . #f(compiled-function (warnings &rest body) #<bytecode 0x11867883d853666e>))))
  macroexp-macroexpand((define-obsolete-variable-alias 'sml/time-format 'display-time-format) ((sml/-debug . #f(compiled-function (fmt &rest r) #<bytecode -0x528c1381ccb3bab>)) (declare-function . byte-compile-macroexpand-declare-function) (eval-when-compile . #f(compiled-function (&rest body) #<bytecode -0xcee878b9e5c479>)) (eval-and-compile . #f(compiled-function (&rest body) #<bytecode 0x31ea4933231cd9b>)) (with-suppressed-warnings . #f(compiled-function (warnings &rest body) #<bytecode 0x11867883d853666e>))))
  byte-compile-recurse-toplevel((define-obsolete-variable-alias 'sml/time-format 'display-time-format) #<subr F616e6f6e796d6f75732d6c616d626461_anonymous_lambda_45>)
  byte-compile-toplevel-file-form((define-obsolete-variable-alias 'sml/time-format 'display-time-format))
  #<subr F616e6f6e796d6f75732d6c616d626461_anonymous_lambda_43>(#<buffer  *Compiler Input*>)
  byte-compile-from-buffer(#<buffer  *Compiler Input*>)
  byte-compile-file("c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019...")
  #f(compiled-function (filename) "Byte-compile FILENAME spilling data from the byte compiler." #<bytecode 0x8fb180dc298647e>)("c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019...")
  apply(#f(compiled-function (filename) "Byte-compile FILENAME spilling data from the byte compiler." #<bytecode 0x8fb180dc298647e>) "c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019..." nil)
  comp-spill-lap-function("c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019...")
  comp-spill-lap("c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019...")
  #f(compiled-function (pass) #<bytecode 0x1a1ac110a850427c>)(comp-spill-lap)
  mapc(#f(compiled-function (pass) #<bytecode 0x1a1ac110a850427c>) (comp-spill-lap comp-limplify comp-fwprop comp-call-optim comp-ipa-pure comp-add-cstrs comp-fwprop comp-dead-code comp-tco comp-fwprop comp-remove-type-hints comp-final))
  comp--native-compile("c:/Users/xxx/.emacs.d/elpa/smart-mode-line-2019..." t)
  load-with-code-conversion("c:/Users/xxx/AppData/Local/Temp/emacs-async-com..." "c:/Users/xxx/AppData/Local/Temp/emacs-async-com..." nil t)
  command-line-1(("-l" "c:/Users/xxx/AppData/Local/Temp/emacs-async-com..."))
  command-line()
  normal-top-level()

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