我在R中有一个程序调用了几个Fortran例程，这些例程都是openMP启用的。有两个Fortran例程sub_1和sub_2。第一个在R函数中被调用两次，而第二个被调用一次。除了一些小事以外，这两个例程几乎完全相同。我称之为第一个例程，然后是第二个例程，然后是第一个例程。但是，如果我让它们都启用了openMP，那么当它第二次使用第一个fortran例程时，该函数会停止执行任何操作（没有错误或停止执行，只是坐在那里）。
如果我在sub_1中禁用openMP，那么一切运行正常。如果我在sub_2中禁用openMP，那么它在sub_1的第二次使用时会再次以相同的方式挂起。这很奇怪，因为它显然可以完成第一次使用。
我认为这可能与线程没有正确关闭或某事（我不太了解openMP）。然而，另一个奇怪的是调用这三个例程的R函数被调用了四次，如果我只在sub_2中启用openMP，那么这很好（即第二次，第三次等调用{{ 1}}不挂起）。我不知道为什么会这样做！作为参考，这是sub_2：
sub_1有没有人知道为什么会发生这种情况？
干杯。
我将添加一个我能想到的最小的例子，它确实可以重现问题（顺便说一下，这一定是一个R问题 - 我在这里提出的类型的一个小例子，但写在fortran工作正常） 。所以我在fortran中有上面的代码和以下代码，编译到共享对象subroutine correlation_dd_rad(s_bins,min_s,end_s,n,pos1,dd,r)
!!! INTENT IN !!!!!!!!
integer :: s_bins !Number of separation bins
integer :: N !Number of objects
real(8) :: pos1(3,N) !Cartesian Positions of particles
real(8) :: min_s !The smallest separation calculated.
real(8) :: end_s !The largest separation calculated.
real(8) :: r(N) !The radii of each particle (ascending)
!!! INTENT OUT !!!!!!!
real(8) :: dd(N,s_bins) !The binned data.
!!! LOCAL !!!!!!!!!!!!
integer :: i,j !Iterators
integer :: bin
real(8) :: d !Distance between particles.
real(8) :: dr,mins,ends
real(8),parameter :: pi = 3.14159653589
integer :: counter
dd(:,:) = 0.d0
dr = (end_s-min_s)/s_bins
!Perform the separation binning
mins = min_s**2
ends = end_s**2
counter = 1000
!$OMP parallel do private(d,bin,j)
do i=1,N
!$omp critical (count_it)
counter = counter - 1
!$omp end critical (count_it)
if(counter==0)then
counter = 1000
write(*,*) "Another Thousand"
end if
do j=i+1,N
if(r(j)-r(i) .GT. end_s)then
exit
end if
d=(pos1(1,j)-pos1(1,i))**2+&
&(pos1(2,j)-pos1(2,i))**2+&
&(pos1(3,j)-pos1(3,i))**2
if(d.LT.ends .AND. d.GT.mins)then
d = Sqrt(d)
bin = Floor((d-min_s)/dr)+1
dd(i,bin) = dd(i,bin)+1.d0
dd(j,bin) = dd(j,bin)+1.d0
end if
end do
end do
!$OMP end parallel do
write(*,*) "done"
end subroutine
：
correlate.so然后在R中，我有以下函数 - 前两个函数只包含上面的fortran代码。第三种方式与我的实际代码类似：
subroutine correlation_dr_rad(s_bins,min_s,end_s,n,pos1,n2,pos2,dd,r1,r2)
!!! INTENT IN !!!!!!!!
integer :: s_bins !Number of separation bins
integer :: N !Number of objects
integer :: n2
real(8) :: pos1(3,N) !Cartesian Positions of particles
real(8) :: pos2(3,n2) !random particles
real(8) :: end_s !The largest separation calculated.
real(8) :: min_s !The smallest separation
real(8) :: r1(N),r2(N2) !The radii of particles (ascending)
!!! INTENT OUT !!!!!!!
real(8) :: dd(N,s_bins) !The binned data.
!!! LOCAL !!!!!!!!!!!!
integer :: i,j !Iterators
integer :: bin
real(8) :: d !Distance between particles.
real(8) :: dr,mins,ends
real(8),parameter :: pi = 3.14159653589
integer :: counter
dd(:,:) = 0.d0
dr = (end_s-min_s)/s_bins
!Perform the separation binning
mins = min_s**2
ends = end_s**2
write(*,*) "Got just before parallel dr"
counter = 1000
!$OMP parallel do private(d,bin,j)
do i=1,N
!$OMP critical (count)
counter = counter - 1
!$OMP end critical (count)
if(counter==0)then
write(*,*) "Another thousand"
counter = 1000
end if
do j=1,N2
if(r2(j)-r1(i) .GT. end_s)then
exit
end if
d=(pos1(1,j)-pos2(1,i))**2+&
&(pos1(2,j)-pos2(2,i))**2+&
&(pos1(3,j)-pos2(3,i))**2
if(d.GT.mins .AND. d.LT.ends)then
d = Sqrt(d)
bin = Floor((d-min_s)/dr)+1
dd(i,bin) = dd(i,bin)+1.d0
end if
end do
end do
!$OMP end parallel do
write(*,*) "Done"
end subroutine
运行这个我得到输出：
correlate_dd_rad = function(pos,r,min_r,end_r,bins){
#A wrapper for the fortran routine of the same name.
dyn.load('correlate.so')
out = .Fortran('correlation_dd_rad',
s_bins = as.integer(bins),
min_s = as.double(min_r),
end_s = as.double(end_r),
n = as.integer(length(r)),
pos = as.double(t(pos)),
dd = matrix(0,length(r),bins), #The output matrix.
r = as.double(r))
dyn.unload('correlate.so')
return(out$dd)
}
correlate_dr_rad = function(pos1,r1,pos2,r2,min_r,end_r,bins){
#A wrapper for the fortran routine of the same name
N = length(r1)
N2 = length(r2)
dyn.load('correlate.so')
out = .Fortran('correlation_dr_rad',
s_bins = as.integer(bins),
min_s = as.double(min_r),
end_s = as.double(end_r),
n = N,
pos1 = as.double(t(pos1)),
n2 = N2,
pos2 = as.double(t(pos2)),
dr = matrix(0,nrow=N,ncol=bins),
r1 = as.double(r1),
r2 = as.double(r2))
dyn.unload('correlate.so')
return(out$dr)
}
the_calculation = function(){
#Generate some data to use
pos1 = matrix(rnorm(30000),10000,3)
pos2 = matrix(rnorm(30000),10000,3)
#Find the radii
r1 = sqrt(pos1[,1]^2 + pos1[,2]^2+pos1[,3]^2)
r2 = sqrt(pos2[,1]^2 + pos2[,2]^2+pos2[,3]^2)
#usually sort them but it doesn't matter here.
#Now call the functions
print("Calculating the data-data pairs")
dd = correlate_dd_rad(pos=pos1,r=r1,min_r=0.001,end_r=0.8,bins=15)
print("Calculating the data-random pairs")
dr = correlate_dr_rad(pos1,r1,pos2,r2,min_r=0.001,end_r=0.8,bins=15)
print("Calculating the random-random pairs")
rr = correlate_dd_rad(pos=pos2,r=r2,min_r=0.001,end_r=0.8,bins=15)
#Now we would do something with it but I don't care in this example.
print("Done")
}
然后它只是坐在那里......实际上，运行它几次表明它每次都会挂起。有时它通过第二次拨打 [1] "Calculating the data-data pairs"
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
Another Thousand
done
[1] "Calculating the data-random pairs"
Got just before parallel dr
Another thousand
Another thousand
和其他人的大部分时间只能通过调用correlate_dd_rad的一半。
答案 0 :(得分：1)
我不确定这是否能解决您的问题，但确实是一个错误。在子程序correlation_dd_rad中，当您打算关闭并行区域时，实际上是在发表评论。更清楚的是：
!OMP end parallel do
应转换为：
!$OMP end parallel do
附注：
use omp_lib atomic构造（请参阅最新OpenMP规范的section 2.8.5）以原子方式访问特定存储位置，而不是critical构造critical构造的名称命名为（规范的第2.8.2节）所有没有名称的关键构造都被视为具有相同的未指定名称。