Hi, Dr Stark

I find it seems that Parallel execution do not work in DiffBind when working under Windows system

library(DiffBind)
library(BiocParallel)

> tamoxifen <- dba(sampleSheet="tamoxifen.csv")
BT4741 BT474 ER Resistant Full-Media 1 bed
BT4742 BT474 ER Resistant Full-Media 2 bed
MCF71 MCF7 ER Responsive Full-Media 1 bed
MCF72 MCF7 ER Responsive Full-Media 2 bed
MCF73 MCF7 ER Responsive Full-Media 3 bed
T47D1 T47D ER Responsive Full-Media 1 bed
T47D2 T47D ER Responsive Full-Media 2 bed
MCF7r1 MCF7 ER Resistant Full-Media 1 bed
MCF7r2 MCF7 ER Resistant Full-Media 2 bed
ZR751 ZR75 ER Responsive Full-Media 1 bed
ZR752 ZR75 ER Responsive Full-Media 2 bed
> tamoxifen <- dba.count(tamoxifen, summits=250)
Computing summits...
Sample: reads/Chr18_BT474_ER_1.bam125 
Sample: reads/Chr18_BT474_ER_2.bam125 
Sample: reads/Chr18_MCF7_ER_1.bam125 
Sample: reads/Chr18_MCF7_ER_2.bam125 
Sample: reads/Chr18_MCF7_ER_3.bam125 
Sample: reads/Chr18_T47D_ER_1.bam125 
Sample: reads/Chr18_T47D_ER_2.bam125 
Sample: reads/Chr18_TAMR_ER_1.bam125 
Sample: reads/Chr18_TAMR_ER_2.bam125 
Sample: reads/Chr18_ZR75_ER_1.bam125 
Sample: reads/Chr18_ZR75_ER_2.bam125 
Sample: reads/Chr18_BT474_input.bam125 
Sample: reads/Chr18_MCF7_input.bam125 
Sample: reads/Chr18_T47D_input.bam125 
Sample: reads/Chr18_TAMR_input.bam125 
Sample: reads/Chr18_ZR75_input.bam125 
Re-centering peaks...
Reads will be counted as Single-end.
Sample: reads/Chr18_BT474_ER_1.bam125 
Sample: reads/Chr18_BT474_ER_2.bam125 
Sample: reads/Chr18_MCF7_ER_1.bam125 
Sample: reads/Chr18_MCF7_ER_2.bam125 
Sample: reads/Chr18_MCF7_ER_3.bam125 
Sample: reads/Chr18_T47D_ER_1.bam125 
Sample: reads/Chr18_T47D_ER_2.bam125 
Sample: reads/Chr18_TAMR_ER_1.bam125 
Sample: reads/Chr18_TAMR_ER_2.bam125 
Sample: reads/Chr18_ZR75_ER_1.bam125 
Sample: reads/Chr18_ZR75_ER_2.bam125 
Sample: reads/Chr18_BT474_input.bam125 
Sample: reads/Chr18_MCF7_input.bam125 
Sample: reads/Chr18_T47D_input.bam125 
Sample: reads/Chr18_TAMR_input.bam125 
Sample: reads/Chr18_ZR75_input.bam125 
Warning messages:
1: Parallel execution unavailable: executing serially. 
2: UNKNOWN PARALLEL PACKAGE: 0

sessionInfo()
#> R version 4.0.2 (2020-06-22)
#> Platform: x86_64-w64-mingw32/x64 (64-bit)
#> Running under: Windows 10 x64 (build 19041)
#> 
#> Matrix products: default
#> 
#> locale:
#> [1] LC_COLLATE=Chinese (Simplified)_China.936 
#> [2] LC_CTYPE=Chinese (Simplified)_China.936   
#> [3] LC_MONETARY=Chinese (Simplified)_China.936
#> [4] LC_NUMERIC=C                              
#> [5] LC_TIME=Chinese (Simplified)_China.936    
#> 
#> attached base packages:
#> [1] stats     graphics  grDevices utils     datasets  methods   base     
#> 
#> loaded via a namespace (and not attached):
#>  [1] compiler_4.0.2  magrittr_2.0.1  tools_4.0.2     htmltools_0.5.0
#>  [5] yaml_2.2.1      stringi_1.5.3   rmarkdown_2.6   highr_0.8      
#>  [9] knitr_1.30      stringr_1.4.0   xfun_0.20       digest_0.6.27  
#> [13] rlang_0.4.10    evaluate_0.14
Created on 2021-01-28 by the reprex package (v0.3.0)

Best wishes

Guandong Shang

This is correct. BiocParallel (and by extension DiffBind) does not support multiple parallel operations on Windows platforms.