Lightroom CC: Scroll speed on iMac Pro incredible slow

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  • Problem
  • Updated 2 months ago
  • Acknowledged
  • (Edited)
On my 10 Core iMac Pro with Vega64 and 64 GB RAM the scroll speed of latest Lightroom CC in the library is so ridiculously slow that it just can't be true.
Disable or enable hardware acceleration doesn't change anything.
It's literally unusable like this and I only got 400 images in my library.
When flicking the scroll area of my mouse it takes 1-2 seconds until it moves.
Anyone else experiencing this? How can this be true?
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Posted 8 months ago

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Photo of Rikk Flohr

Rikk Flohr, Official Rep

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Greetings Striatum,

What size/resolution monitor do you have?
Is the Syncing Icon showing everything synced and local?
Do you store your images locally or have everything set to be in cloud with only as-needed downloads?
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Fjölnir Ásgeirsson

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He said he's running an iMac Pro.. it has a 27 inch 5k display.

I have the same issue. Scrolling is unusably slow. Originals synced on internal SSD

Lightroom CC version: 2.0 [ 20180919-1627-7b5e24e ] (Sep 20 2018)Operating system: Mac OS 10
OS Version: 10.14 [1]
Application architecture: x64
Logical processor count: 16
Processor speed: 3.2 GHz
Built-in memory: 65,536.0 MB
Real memory available to Lightroom CC: 65,536.0 MB
Real memory used by Lightroom CC: 1,545.5 MB (2.3%)
Virtual memory used by Lightroom CC: 2,499.3 MB
Memory cache size: 948.9 MB
Internal Camera Raw revision: 61
Maximum thread count used by Camera Raw: 9
Camera Raw SIMD optimization: SSE2,AVX,AVX2
Camera Raw virtual memory: 22MB / 32767MB (0%)
Camera Raw real memory: 22MB / 65536MB (0%)
Displays: 1) 5120x2880

Graphics Processor Info: 
Metal: AMD Radeon Pro Vega 64

AudioDeviceIOBlockSize: 512
AudioDeviceName: iMac Pro Speakers
AudioDeviceNumberOfChannels: 2
AudioDeviceSampleRate: 44100
Build: Uninitialized
CoreImage: true
GL_RENDERER: AMD Radeon Pro Vega 64 OpenGL Engine
GL_VENDOR: ATI Technologies Inc.
GL_VERSION: 2.1 ATI-2.2.6
OGLEnabled: true
GL_EXTENSIONS: GL_ARB_color_buffer_float GL_ARB_depth_buffer_float GL_ARB_depth_clamp GL_ARB_depth_texture GL_ARB_draw_buffers GL_ARB_draw_elements_base_vertex GL_ARB_draw_instanced GL_ARB_fragment_program GL_ARB_fragment_program_shadow GL_ARB_fragment_shader GL_ARB_framebuffer_object GL_ARB_framebuffer_sRGB GL_ARB_half_float_pixel GL_ARB_half_float_vertex GL_ARB_imaging GL_ARB_instanced_arrays GL_ARB_multisample GL_ARB_multitexture GL_ARB_occlusion_query GL_ARB_pixel_buffer_object GL_ARB_point_parameters GL_ARB_point_sprite GL_ARB_provoking_vertex GL_ARB_seamless_cube_map GL_ARB_shader_objects GL_ARB_shader_texture_lod GL_ARB_shading_language_100 GL_ARB_shadow GL_ARB_shadow_ambient GL_ARB_sync GL_ARB_texture_border_clamp GL_ARB_texture_compression GL_ARB_texture_compression_rgtc GL_ARB_texture_cube_map GL_ARB_texture_env_add GL_ARB_texture_env_combine GL_ARB_texture_env_crossbar GL_ARB_texture_env_dot3 GL_ARB_texture_float GL_ARB_texture_mirrored_repeat GL_ARB_texture_non_power_of_two GL_ARB_texture_rectangle GL_ARB_texture_rg GL_ARB_transpose_matrix GL_ARB_vertex_array_bgra GL_ARB_vertex_blend GL_ARB_vertex_buffer_object GL_ARB_vertex_program GL_ARB_vertex_shader GL_ARB_window_pos GL_EXT_abgr GL_EXT_bgra GL_EXT_bindable_uniform GL_EXT_blend_color GL_EXT_blend_equation_separate GL_EXT_blend_func_separate GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_clip_volume_hint GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_depth_bounds_test GL_EXT_draw_buffers2 GL_EXT_draw_range_elements GL_EXT_fog_coord GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample GL_EXT_framebuffer_object GL_EXT_framebuffer_sRGB GL_EXT_geometry_shader4 GL_EXT_gpu_program_parameters GL_EXT_gpu_shader4 GL_EXT_multi_draw_arrays GL_EXT_packed_depth_stencil GL_EXT_packed_float GL_EXT_provoking_vertex GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_separate_specular_color GL_EXT_shadow_funcs GL_EXT_stencil_two_side GL_EXT_stencil_wrap GL_EXT_texture_array GL_EXT_texture_compression_dxt1 GL_EXT_texture_compression_s3tc GL_EXT_texture_env_add GL_EXT_texture_filter_anisotropic GL_EXT_texture_integer GL_EXT_texture_lod_bias GL_EXT_texture_mirror_clamp GL_EXT_texture_rectangle GL_EXT_texture_shared_exponent GL_EXT_texture_sRGB GL_EXT_texture_sRGB_decode GL_EXT_timer_query GL_EXT_transform_feedback GL_EXT_vertex_array_bgra GL_APPLE_aux_depth_stencil GL_APPLE_client_storage GL_APPLE_element_array GL_APPLE_fence GL_APPLE_float_pixels GL_APPLE_flush_buffer_range GL_APPLE_flush_render GL_APPLE_object_purgeable GL_APPLE_packed_pixels GL_APPLE_pixel_buffer GL_APPLE_rgb_422 GL_APPLE_row_bytes GL_APPLE_specular_vector GL_APPLE_texture_range GL_APPLE_transform_hint GL_APPLE_vertex_array_object GL_APPLE_vertex_array_range GL_APPLE_vertex_point_size GL_APPLE_vertex_program_evaluators GL_APPLE_ycbcr_422 GL_ATI_blend_equation_separate GL_ATI_blend_weighted_minmax GL_ATI_separate_stencil GL_ATI_texture_compression_3dc GL_ATI_texture_env_combine3 GL_ATI_texture_float GL_ATI_texture_mirror_once GL_IBM_rasterpos_clip GL_NV_blend_square GL_NV_conditional_render GL_NV_depth_clamp GL_NV_fog_distance GL_NV_light_max_exponent GL_NV_texgen_reflection GL_NV_texture_barrier GL_SGI_color_matrix GL_SGIS_generate_mipmap GL_SGIS_texture_edge_clamp GL_SGIS_texture_lod 

Photo of Striatum


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as told, 5K resolution, everything synced to local SSD
10.14.1 and Lightroom CC 2.0.2 doesn't change a thing


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I have the same problem (Lr CC ver.2) but only after the installation of OSX Mojave, I think that MOJAVE has got an issue with the actual version of LR CC. Is very slow and I can’t use it, it’s impossible! (Macpro 6 core + ssd + 32gb ram)
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Same here - very disappointed. My old 2010 MacPro is faster - yeaahh. Where is the quality control for this software? Hope a fix soon.
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Rikk Flohr, Official Rep

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We have been able to replicate the issue and will be logging an issue for this. Thanks for your reports. 
Photo of William Edwards

William Edwards

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This seems to be the case across all 5K iMacs, not just iMac Pro. Any updates? Thanks
Photo of Darren


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I, too, am eagerly awaiting this bug to be addressed. Currently, Lightroom CC on iMac Pro is unusable due to the delayed scrolling and severe interface lag. I'm having to do everything in Lightroom CC on iPad Pro as a result.
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Julian Manuszewski

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please fix this!  January 2019 - we've now had issues since the iMac pro's launch over a year ago.
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Paulo Abreu

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In fact, I have a MacBook Pro (15-inch, 2016) and I have the same issue. I really don't understand how can Adobe sell a product to the MacOS with such an evident issue.
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Paulo Abreu

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As a workaround, decreasing the window width makes it bearable.
Photo of Armen


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Another workaround which might be acceptable to some, is reducing resolution of the app itself. 

Right click on Lightroom app > Get Info > Launch in low-res mode.

On retina displays you can increase the simulated resolution via Display properties, so that it compensates for some of the resulting UI pixelization.
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Björn Schön

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Same here, not with a iMac Pro, but with a Retina 5k iMac.
The 5k resolution seems to be the main problem here.

Adobe - Apple Photos App is running smooth with  10-thousands of photos, so solve this issue!