Hello fellow ardourists,
I have been using Ardour since a few month now, good soft, thanks @ devs 
I previously used the ardour 5.12 that is shipped with my ubuntu studio distro and have been very happy with it, performs well.
I then decided to support Ardour and so became a subscriber. I then again decided to give the 6 RC a try (since project format is now locked and 6 gives me more possibilities for the Xtouch control surface ).
I downloaded the Official nightly installer and ran the script on my setup, worked like a charm, installed well.
But I have a problem of DSP.
I usually run Ardour 5.12 on 3p/128 @44.1Khz with no problem at all, and when sometimes the project grows i go for 256 , this for midi recording, and then i go at 1024 for mixing.
When I open an old 5.12 project in Ardour 6rc i get a very increased DSP usage, for the same project it nearly doublse, same project, same setup.
I saw a difference in the build options beetween 5.12 from ubuntu studio team and the 6rc from Ardour.org , it’s about libraries to use.
Here are the 2 build setup resumes :
5.12
Build documentation: False
Debuggable build: False
Export all symbols (backtrace): False
Install prefix: /usr
Strict compiler flags: []
Internal Shared Libraries: True
Use External Libraries: True
Library exports hidden: True
Free/Demo copy: FalseALSA DBus Reservation: False
Architecture flags: None
Aubio: True
AudioUnits: False
Build target: x86_64
Canvas Test UI: False
Beatbox test app: False
CoreAudio: False
CoreAudio 10.5 compat: False
Debug RT allocations: False
Debug Symbols: False
Denormal exceptions: False
FLAC: True
FPU optimization: True
Freedesktop files: True
Libjack linking: link
Libjack metadata: True
Lua Binding Doc: False
LV2 UI embedding: True
LV2 support: True
LV2 extensions: True
LXVST support: True
Mac VST support: False
OGG: True
Phone home: False
Process thread timing: False
Program name: Ardour
Samplerate: True
PT format: False
PTW32 Semaphore: False
Threaded WaveViews: True
Translation: True
Unit tests: False
Windows VST support: False
Wiimote support: True
Windows key: Mod4><SuperPortAudio Backend: False
CoreAudio/Midi Backend: False
ALSA Backend: True
Dummy backend: True
JACK Backend: TrueBuilstack: -system-
Mac i386 Architecture: False
Mac ppc Architecture: FalseC compiler flags: [’-I<>’, ‘-Wdate-time’, ‘-D_FORTIFY_SOURCE=2’, ‘-g’, ‘-O2’, ‘-fdebug-prefix-map=<>=.’, ‘-fstack-protector-strong’, ‘-Wformat’, ‘-Werror=format-security’, ‘-DHAVE_RF64_RIFF’, ‘-DWAF_BUILD’, ‘-DNDEBUG’, ‘-fshow-column’, ‘-O3’, ‘-fomit-frame-pointer’, ‘-ffast-math’, ‘-fstrength-reduce’, ‘-pipe’, ‘-DARCH_X86’, ‘-mmmx’, ‘-msse’, ‘-mfpmath=sse’, ‘-DUSE_XMMINTRIN’, ‘-DBUILD_SSE_OPTIMIZATIONS’, ‘-DLXVST_64BIT’, ‘-Wall’, ‘-Wpointer-arith’, ‘-Wcast-qual’, ‘-Wcast-align’, ‘-Wno-unused-parameter’, ‘-DBOOST_SYSTEM_NO_DEPRECATED’, ‘-D_ISOC9X_SOURCE’, ‘-D_LARGEFILE64_SOURCE’, ‘-D_FILE_OFFSET_BITS=64’, ‘-DENABLE_NLS’, ‘-DPROGRAM_NAME=“Ardour”’, ‘-DPROGRAM_VERSION=“5”’, ‘-Wstrict-prototypes’, ‘-Wmissing-prototypes’]
C++ compiler flags: [’-I<>’, ‘-Wdate-time’, ‘-D_FORTIFY_SOURCE=2’, ‘-g’, ‘-O2’, ‘-fdebug-prefix-map=<>=.’, ‘-fstack-protector-strong’, ‘-Wformat’, ‘-Werror=format-security’, ‘-I/usr/include/qm-dsp’, ‘-DHAVE_RF64_RIFF’, ‘-DWAF_BUILD’, ‘-DNDEBUG’, ‘-fshow-column’, ‘-O3’, ‘-fomit-frame-pointer’, ‘-ffast-math’, ‘-fstrength-reduce’, ‘-pipe’, ‘-DARCH_X86’, ‘-mmmx’, ‘-msse’, ‘-mfpmath=sse’, ‘-DUSE_XMMINTRIN’, ‘-DBUILD_SSE_OPTIMIZATIONS’, ‘-DLXVST_64BIT’, ‘-Wall’, ‘-Wpointer-arith’, ‘-Wcast-qual’, ‘-Wcast-align’, ‘-Wno-unused-parameter’, ‘-DBOOST_SYSTEM_NO_DEPRECATED’, ‘-D_ISOC9X_SOURCE’, ‘-D_LARGEFILE64_SOURCE’, ‘-D_FILE_OFFSET_BITS=64’, ‘-DENABLE_NLS’, ‘-DPROGRAM_NAME=“Ardour”’, ‘-DPROGRAM_VERSION=“5”’, ‘-std=c++11’, ‘-DBOOST_NO_AUTO_PTR’, ‘-Woverloaded-virtual’, ‘-Wno-unused-local-typedefs’, ‘-D__STDC_LIMIT_MACROS’, ‘-D__STDC_FORMAT_MACROS’, ‘-DCANVAS_COMPATIBILITY’, ‘-DCANVAS_DEBUG’]
Linker flags: [’-Wl,-Bsymbolic-functions’, ‘-Wl,-z,relro’, ‘-Wl,-z,now’, ‘-Wl,–as-needed’, ‘-Wl,-Bsymbolic-functions’, ‘-Wl,-z,relro’, ‘-Wl,-z,now’, ‘-Wl,–as-needed’]
6rc
Blockquote
Build documentation: False
Debuggable build: True
Export all symbols (backtrace): False
Install prefix: /usr
Strict compiler flags: []
Internal Shared Libraries: True
Use External Libraries: False
Library exports hidden: True
Free/Demo copy: FalseALSA DBus Reservation: True
Architecture flags: None
Aubio: True
AudioUnits: False
Build target: x86_64
Canvas Test UI: False
Beatbox test app: False
CoreAudio: False
CoreAudio 10.5 compat: False
Debug RT allocations: False
Debug Symbols: True
Denormal exceptions: False
FLAC: True
FPU optimization: True
Freedesktop files: False
Libjack linking: weak
Libjack metadata: True
Lua Binding Doc: False
Lua Commandline Tool: True
LV2 UI embedding: True
LV2 support: True
LV2 extensions: True
LXVST support: True
Mac VST support: False
NI-Maschine: False
OGG: True
Phone home: True
Process thread timing: False
Program name: Ardour
Samplerate: True
PT format: True
PTW32 Semaphore: False
Threaded WaveViews: True
Translation: True
Unit tests: False
Use LLD linker: False
Windows VST support: False
Wiimote support: False
Windows key: Mod4><SuperPortAudio Backend: False
CoreAudio/Midi Backend: False
ALSA Backend: True
Dummy backend: True
JACK Backend: True
Pulseaudio Backend: TrueBuildstack: 18e0d3e
Mac i386 Architecture: False
Mac ppc Architecture: FalseC compiler flags: [’-I/home/ardour/linux-x86_64-v5/ardour’, ‘-I/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-DHAVE_RF64_RIFF’, ‘-DWAF_BUILD’, ‘-g’, ‘-std=c99’, ‘-pedantic’, ‘-Wshadow’, ‘-Wall’, ‘-Wcast-align’, ‘-Wextra’, ‘-Wwrite-strings’, ‘-Wunsafe-loop-optimizations’, ‘-Wlogical-op’, ‘-fshow-column’, ‘-DARCH_X86’, ‘-mmmx’, ‘-msse’, ‘-mfpmath=sse’, ‘-DUSE_XMMINTRIN’, ‘-DBUILD_SSE_OPTIMIZATIONS’, ‘-DLXVST_64BIT’, ‘-Wall’, ‘-Wpointer-arith’, ‘-Wcast-qual’, ‘-Wcast-align’, ‘-Wno-unused-parameter’, ‘-DBOOST_SYSTEM_NO_DEPRECATED’, ‘-D_ISOC9X_SOURCE’, ‘-D_LARGEFILE64_SOURCE’, ‘-D_FILE_OFFSET_BITS=64’, ‘-DPROGRAM_NAME=“Ardour”’, ‘-DPROGRAM_VERSION=“6”’, ‘-Wstrict-prototypes’, ‘-Wmissing-prototypes’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtk-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pango-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atk-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairo’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pixman-1’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdk-pixbuf-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/libpng16’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/harfbuzz’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glib-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glib-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/uuid’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/freetype2’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtkmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtkmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atkmm-1.6’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-unix-print-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdkmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gdkmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/giomm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/giomm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pangomm-1.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/pangomm-1.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glibmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glibmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairomm-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/cairomm-1.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/sigc+±2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/sigc+±2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtk-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pango-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atk-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairo’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pixman-1’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdk-pixbuf-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/libpng16’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/harfbuzz’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glib-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glib-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/uuid’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/freetype2’]
C++ compiler flags: [’-I/home/ardour/linux-x86_64-v5/ardour’, ‘-I/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-DHAVE_RF64_RIFF’, ‘-DWAF_BUILD’, ‘-g’, ‘-ansi’, ‘-Wnon-virtual-dtor’, ‘-Woverloaded-virtual’, ‘-fstrict-overflow’, ‘-Wall’, ‘-Wcast-align’, ‘-Wextra’, ‘-Wwrite-strings’, ‘-Wunsafe-loop-optimizations’, ‘-Wlogical-op’, ‘-fshow-column’, ‘-DARCH_X86’, ‘-mmmx’, ‘-msse’, ‘-mfpmath=sse’, ‘-DUSE_XMMINTRIN’, ‘-DBUILD_SSE_OPTIMIZATIONS’, ‘-DLXVST_64BIT’, ‘-Wall’, ‘-Wpointer-arith’, ‘-Wcast-qual’, ‘-Wcast-align’, ‘-Wno-unused-parameter’, ‘-DBOOST_SYSTEM_NO_DEPRECATED’, ‘-D_ISOC9X_SOURCE’, ‘-D_LARGEFILE64_SOURCE’, ‘-D_FILE_OFFSET_BITS=64’, ‘-DPROGRAM_NAME=“Ardour”’, ‘-DPROGRAM_VERSION=“6”’, ‘-std=c++11’, ‘-DBOOST_NO_AUTO_PTR’, ‘-Woverloaded-virtual’, ‘-Wno-unused-local-typedefs’, ‘-D__STDC_LIMIT_MACROS’, ‘-D__STDC_FORMAT_MACROS’, ‘-DCANVAS_COMPATIBILITY’, ‘-DCANVAS_DEBUG’, ‘-DBOOST_ERROR_CODE_HEADER_ONLY’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtk-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pango-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atk-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairo’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pixman-1’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdk-pixbuf-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/libpng16’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/harfbuzz’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glib-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glib-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/uuid’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/freetype2’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtkmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtkmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atkmm-1.6’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-unix-print-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gtk-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdkmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gdkmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/giomm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/giomm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pangomm-1.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/pangomm-1.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glibmm-2.4’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glibmm-2.4/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairomm-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/cairomm-1.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/sigc+±2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/sigc+±2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/gtk-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pango-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/atk-1.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/cairo’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/pixman-1’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/gdk-pixbuf-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/libpng16’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/harfbuzz’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/glib-2.0’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/lib/glib-2.0/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/uuid’, ‘-isystem’, ‘/home/ardour/linux-x86_64-v5/gtk/inst/include/freetype2’]
Linker flags: [’-L/home/ardour/linux-x86_64-v5/gtk/inst/lib’, ‘’]
My laptop is T440p lenovo (4th gen corei5 + 8gb ram + SSD) running ubuntu studio 19.10, xfce 4 as DE.
Is this behavior normal at all?, i feel like abnormal/weird, as the gap beetween the 2 is too big in my opinion.
I think having heard that the code is new in Ardour 6, so maybe it’s normal behavior.
What should I supply in order to help you fellows help me ?
EDIT: sorry did not found the Code template in order to reduce my post height,if someone is kind enough to show me how to it will be a pleasure to reduce that post lenght 

