mpibook_Antonov

MPI_START(REQUEST, IERR) INTEGER REQUEST, IERR

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MPI_STARTALL(COUNT, REQUESTS, IERR) INTEGER COUNT, REQUESTS, IERR

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< hlebqb_ hl g_[ehdbjmxsbo hi_jZpbc ih aZ\_jr_gbb \uiheg_gby hi_jZpbb aZims_gghc ijb ihfhsb hleh`_ggh]h aZijhkZ gZ \aZbfh^_ckl\b_ agZq_gb_ iZjZf_ljZ REQUEST (REQUESTS khojZgy_lky b fh`_l bkihevah\Zlvky \ ^Zevg_cr_f

MPI_REQUEST_FREE(REQUEST, IERR) INTEGER REQUEST, IERR

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	prev = rank - 1
	next = rank + 1
	if(rank .eq. 0) prev = size - 1
	if(rank .eq. size - 1) next = 0
	call MPI_RECV_INIT(rbuf(1), 1, MPI_REAL, prev, 5,
&	MPI_COMM_WORLD, reqs(1), ierr)
	call MPI_RECV_INIT(rbuf(2), 1, MPI_REAL, next, 6,
&	MPI_COMM_WORLD, reqs(2), ierr)
	call MPI_SEND_INIT(sbuf(1), 1, MPI_REAL, prev, 6,
&	MPI_COMM_WORLD, reqs(3), ierr)
	call MPI_SEND_INIT(sbuf(2), 1, MPI_REAL, next, 5,
&	MPI_COMM_WORLD, reqs(4), ierr)
	do i=...
	sbuf(1)=...
	sbuf(2)=...
	call MPI_STARTALL(4, reqs, ierr)
	...
	call MPI_WAITALL(4, reqs, stats, ierr);
	...
	end do

31

call MPI_REQUEST_FREE(reqs(1), ierr) call MPI_REQUEST_FREE(reqs(2), ierr) call MPI_REQUEST_FREE(reqs(3), ierr) call MPI_REQUEST_FREE(reqs(4), ierr)

Lmibdh\u_ kblmZpbb GHDGORFN

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ijhp_kk 0:	ijhp_kk 1:
MPI_RECV hl ijhp_kkZ	MPI_RECV hl ijhp_kkZ	<hagbdZ_l lmibd
MPI_SEND ijhp_kkm	MPI_SEND ijhp_kkm
ijhp_kk 0:	ijhp_kk 1:	Fh`_l
MPI_SEND ijhp_kkm	MPI_SEND ijhp_kkm	\hagbdgmlv
MPI_RECV hl ijhp_kkZ	MPI_RECV hl ijhp_kkZ	lmibd

JZkkfhljbf jZaebqgu_ kihkh[u jZaj_r_gby lmibdh\uo kblmZpbc

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ijhp_kk 0:	ijhp_kk 1:	Lmibd
MPI_SEND ijhp_kkm	MPI_RECV hl ijhp_kkZ	g_ \hagbdZ_l
MPI_RECV hl ijhp_kkZ	MPI_SEND ijhp_kkm

32

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Ijhp_kk 0:	ijhp_kk 1:
MPI_SEND ijhp_kkm	MPI_IRECV hl ijhp_kkZ	Lmibd
MPI_RECV hl ijhp_kkZ	MPI_SEND ijhp_kkm	g_ \hagbdZ_l
	MPI_WAIT

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3.Lj_lvbf \ZjbZglhf jZaj_r_gby lmibdh\hc kblmZpbb fh`_l [ulv bkihevah\Zgb_ ijhp_^mju MPI_SENDRECV.

MPI_SENDRECV(SBUF, SCOUNT, STYPE, DEST, STAG, RBUF, RCOUNT, RTYPE, SOURCE, RTAG, COMM, STATUS, IERR)

<type> SBUF(*), RBUF(*)

INTEGER SCOUNT, STYPE, DEST, STAG, RCOUNT, RTYPE, SOURCE, RTAG, COMM, STATUS(MPI_STATUS_SIZE), IERR

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33

MPI_SENDRECV_REPLACE(BUF, COUNT, DATATYPE, DEST, STAG, SOURCE, RTAG, COMM, STATUS, IERR)

<type> BUF(*)

INTEGER COUNT, DATATYPE, DEST, STAG, SOURCE, RTAG, COMM, STATUS(MPI_STATUS_SIZE), IERR

Kh\f_s_ggu_ ijb_f b i_j_^ZqZ khh[s_gbc k [ehdbjh\dhc q_j_a h[sbc [mn_j BUF IjbgbfZ_fh_ khh[s_gb_ g_ ^he`gh ij_\urZlv ih jZaf_jm hl- ijZ\ey_fh_ khh[s_gb_ Z i_j_^Z\Z_fu_ b ijbgbfZ_fu_ ^Zggu_ ^he`gu [ulv h^gh]h lbiZ

< ke_^mxs_f ijbf_j_ hi_jZpbb ^\mgZijZ\e_ggh]h h[f_gZ k khk_^gbfb ijh- p_kkZfb \ dhevp_\hc lhiheh]bb ijhba\h^ylky ijb ihfhsb ^\mo \uah\h\ ijh- p_^mju MPI_SENDRECV Ijb wlhf ]ZjZglbjh\Zggh g_ \hagbdZ_l lmibdh\hc kb- lmZpbb

	program example12
	include 'mpif.h'
	integer ierr, rank, size, prev, next, buf(2)
	integer status1(MPI_STATUS_SIZE), status2(MPI_STATUS_SIZE)
	call MPI_INIT(ierr)
	call MPI_COMM_SIZE(MPI_COMM_WORLD, size, ierr)
	call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
	prev = rank - 1
	next = rank + 1
	if(rank .eq. 0) prev = size - 1
	if(rank .eq. size - 1) next = 0
	call MPI_SENDRECV(rank, 1, MPI_INTEGER, prev, 6,
&	buf(2), 1, MPI_INTEGER, next, 6,
&	MPI_COMM_WORLD, status2, ierr)
	call MPI_SENDRECV(rank, 1, MPI_INTEGER, next, 5,
&	buf(1), 1, MPI_INTEGER, prev, 5,
&	MPI_COMM_WORLD, status1, ierr)
	print *, ‘process ’, rank,
&	‘ prev=’, buf(1), ‘ next=’, buf(2)
	call MPI_FINALIZE(ierr)
	end

AZ^Zgby

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•DZd ijbgylv ex[h_ khh[s_gb_ hl ex[h]h ijhp_kkZ"

34

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•Fh`gh eb ijb ihkued_ khh[s_gby bkihevah\Zlv dhgklZglu

MPI_ANY_SOURCE b MPI_ANY_TAG?

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•KjZ\gblv wnn_dlb\ghklv j_ZebaZpbb jZaebqguo \b^h\ i_j_kuehd ^Zg-

guo k [ehdbjh\dhc MPI_SEND, MPI_BSEND, MPI_SSEND, MPI_RSEND f_-

`^m ^\mfy \u^_e_ggufb ijhp_kkhjZfb

•Qlh hagZqZ_l aZ\_jr_gb_ hi_jZpbb ^ey jZaebqguo \b^h\ i_j_kuedb ^Zgguo k [ehdbjh\dhc"

•Hij_^_eblv fZdkbfZevgh ^himklbfmx ^ebgm ihkueZ_fh]h khh[s_gby \ ^Zgghc j_ZebaZpbb MPI.

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•Hij_^_eblv \hafh`gh eb \ ^Zgghc j_ZebaZpbb MPI kh\f_s_gb_ Zkbgojhgguo i_j_kuehd ^Zgguo b \uiheg_gby Zjbnf_lbq_kdbo hi_jZpbc

•DZd k ihfhsvx ijhp_^mju MPI_TEST kfh^_ebjh\Zlv nmgdpbhgZev- ghklv ijhp_^mju MPI_WAIT?

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•Qlh ijhbahc^_l ijb hkms_kl\e_gbb h[f_gZ ^Zggufb k ijhp_kkhf

MPI_PROC_NULL?

•J_Zebah\Zlv ijb ihfhsb ihkuedb khh[s_gbc lbiZ lhqdZ-lhqdZ ke_^mxsb_ ko_fu dhffmgbdZpbb ijhp_kkh\

o i_j_^ZqZ ^Zgguo ih dhevpm ^\Z \ZjbZglZ wklZn_lgZy iZehqdZhq_j_^ghc ijhp_kk ^h`b^Z_lky khh[s_gby hl ij_^u^ms_]h b ihlhf ihkueZ_l ke_^mxs_fm b k^\b] h^gh\j_f_ggu_ ihkuedZ b ijb_f khh[s_gbc

o master-VODYH \k_ ijhp_kku h[sZxlky k h^gbf \u^_e_gguf ijhp_kkhf

o i_j_kuedZ ^Zgguo hl dZ`^h]h ijhp_kkZ dZ`^hfm

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35

•Hij_^_eblv \ub]jur dhlhjuc fh`gh ihemqblv ijb bkihevah\Zgbb hl- eh`_gguo aZijhkh\ gZ \aZbfh^_ckl\b_

•KjZ\gblv wnn_dlb\ghklv j_ZebaZpbb nmgdpbb MPI_SENDRECV k fh^_ebjh\Zgb_f lhc `_ nmgdpbhgZevghklb ijb ihfhsb g_[ehdbjmx- sbo hi_jZpbc

Dhee_dlb\gu_ \aZbfh^_ckl\by ijhp_kkh\

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MPI_BARRIER(COMM, IERR) INTEGER COMM, IERR

Ijhp_^mjZ bkihevam_lky ^ey [Zjv_jghc kbgojhgbaZpbb ijhp_kkh\ JZ[hlZ ijhp_kkh\ [ehdbjm_lky ^h l_o ihj ihdZ \k_ hklZ\rb_ky ijhp_kku dhffmgbdZlhjZ COMM g_ \uihegyl wlm ijhp_^mjm Lhevdh ihke_ lh]h dZd ihke_^gbc ijhp_kk dhffmgbdZlhjZ \uihegbl ^Zggmx ijhp_^mjm \k_ ijhp_kku [m^ml jZa[ehdbjh\Zgu b ijh^he`Zl \uiheg_gb_ ^Zevr_ >ZggZy ijhp_^mjZ y\ey_lky dhee_dlb\ghc <k_ ijhp_kku ^he`gu \ua\Zlv

36

MPI_BARRIER ohly j_Zevgh bkiheg_ggu_ \uah\u jZaebqgufb ijhp_kkZfb dhffmgbdZlhjZ fh]ml [ulv jZkiheh`_gu \ jZaguo f_klZo ijh]jZffu

< ke_^mxs_f ijbf_j_ nmgdpbhgZevghklv ijhp_^mju MPI_BARRIER fh^_eb- jm_lky ijb ihfhsb hleh`_gguo aZijhkh\ gZ \aZbfh^_ckl\b_ >ey mkj_^g_gby j_amevlZlh\ ijhba\h^blky NTIMES hi_jZpbc h[f_gZ \ jZfdZo dZ`^hc ba gbo \k_ ijhp_kku ^he`gu ihkeZlv khh[s_gb_ ijhp_kkm k ghf_jhf 0 ihke_ q_]h ihemqblv hl g_]h hl\_lguc kb]gZe hagZqZxsbc qlh \k_ ijhp_kku ^hreb ^h wlhc lhqdb \ ijh]jZff_ Bkihevah\Zgb_ hleh`_gguo aZijhkh\ iha\hey_l bgbpbZebabjh\Zlv ihkuedm ^Zgguo lhevdh h^bg jZa Z aZl_f bkihevah\Zlv gZ dZ`^hc bl_jZpbb pbdeZ >Ze__ \j_fy gZ fh^_ebjh\Zgb_ kjZ\gb\Z_lky kh \j_f_g_f gZ kbgojhgbaZpbx ijb ihfhsb kZfhc klZg^Zjlghc ijhp_^mju MPI_BARRIER.

	program example13
	include 'mpif.h'
	integer ierr, rank, size, MAXPROC, NTIMES, i, it
	parameter (MAXPROC = 128, NTIMES = 10000)
	integer ibuf(MAXPROC)
	double precision time_start, time_finish
	integer req(2*MAXPROC), statuses(MPI_STATUS_SIZE, MAXPROC)
	call MPI_INIT(ierr)
	call MPI_COMM_SIZE(MPI_COMM_WORLD, size, ierr)
	call MPI_COMM_RANK(MPI_COMM_WORLD, rank, ierr)
	if(rank .eq. 0) then
	do i = 1, size-1
	call MPI_RECV_INIT(ibuf(i), 0, MPI_INTEGER, i, 5,
&	MPI_COMM_WORLD, req(i), ierr)
	call MPI_SEND_INIT(rank, 0, MPI_INTEGER, i, 6,
&	MPI_COMM_WORLD, req(size+i),
&	ierr)
	end do
	time_start = MPI_WTIME(ierr)
	do it = 1, NTIMES
	call MPI_STARTALL(size-1, req, ierr)
	call MPI_WAITALL(size-1, req, statuses, ierr)
	call MPI_STARTALL(size-1, req(size+1), ierr)
	call MPI_WAITALL(size-1, req(size+1), statuses,
&	ierr)
	end do
	else
	call MPI_RECV_INIT(ibuf(1), 0, MPI_INTEGER, 0, 6,
&	MPI_COMM_WORLD, req(1), ierr)
	call MPI_SEND_INIT(rank, 0, MPI_INTEGER, 0, 5,
&	MPI_COMM_WORLD, req(2), ierr)
	time_start = MPI_WTIME(ierr)
	do it = 1, NTIMES
	call MPI_START(req(2), ierr)
	call MPI_WAIT(req(2), statuses, ierr)
	call MPI_START(req(1), ierr)

37

call MPI_WAIT(req(1), statuses, ierr) end do

end if

time_finish = MPI_WTIME(ierr)-time_start print *, 'rank = ', rank, ' all time = ',

&(time_finish)/NTIMES

time_start = MPI_WTIME(ierr) do it = 1, NTIMES

call MPI_BARRIER(MPI_COMM_WORLD,ierr) enddo

time_finish = MPI_WTIME(ierr)-time_start print *, 'rank = ', rank, ' barrier time = ',

& (time_finish)/NTIMES call MPI_FINALIZE(ierr)

end

MPI_BCAST(BUF, COUNT, DATATYPE, ROOT, COMM, IERR) <type> BUF(*)

INTEGER COUNT, DATATYPE, ROOT, COMM, IERR

JZkkuedZ COUNT we_f_glh\ ^Zgguo lbiZ DATATYPE ba fZkkb\Z BUF hl ijhp_kkZ ROOT \k_f ijhp_kkZf ^Zggh]h dhffmgbdZlhjZ COMM, \dexqZy kZf jZkkueZxsbc ijhp_kk Ijb \ha\jZl_ ba ijhp_^mju kh^_j`bfh_ [mn_jZ BUF ijhp_kkZ ROOT [m^_l kdhibjh\Zgh \ ehdZevguc [mn_j dZ`^h]h ijhp_kkZ dhffmgbdZlhjZ COMM AgZq_gby iZjZf_ljh\ COUNT, DATATYPE, ROOT b COMM ^he`gu [ulv h^bgZdh\ufb m \k_o ijhp_kkh\

Ke_^mxsZy ko_fZ beexkljbjm_l ^_ckl\b_ ijhp_^mju MPI_BCAST A^_kv lZd`_ dZd b \ ^Zevg_crbo ko_fZo ih \_jlbdZeb bah[jZ`Zxlky jZagu_ ijh- p_kku mqZkl\mxsb_ \ dhee_dlb\ghc hi_jZpbb Z ih ]hjbahglZeb – jZkiheh- `_ggu_ gZ gbo [ehdb ^Zgguo

GZijbf_j ^ey lh]h qlh[u i_j_keZlv hl ijhp_kkZ 2 \k_f hklZevguf ijhp_k- kZf ijbeh`_gby fZkkb\ buf ba 100 p_ehqbke_gguo we_f_glh\ gm`gh qlh[u \h \k_o ijhp_kkZo \klj_lbeky ke_^mxsbc \uah\

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	call MPI_BCAST(buf, 100, MPI_INTEGER,
&	2, MPI_COMM_WORLD, ierr)

MPI_GATHER(SBUF, SCOUNT, STYPE, RBUF, RCOUNT, RTYPE, ROOT, COMM, IERR)

<type> SBUF(*), RBUF(*)

INTEGER SCOUNT, STYPE, RCOUNT, RTYPE, ROOT, COMM, IERR

K[hjdZ SCOUNT we_f_glh\ ^Zgguo lbiZ STYPE ba fZkkb\h\ SBUF kh \k_o ijh- p_kkh\ dhffmgbdZlhjZ COMM \ [mn_j_ RBUF ijhp_kkZ ROOT DZ`^uc ijhp_kk \dexqZy ROOT ihkueZ_l kh^_j`bfh_ k\h_]h [mn_jZ SBUF ijhp_kkm ROOT Kh- [bjZxsbc ijhp_kk khojZgy_l ^Zggu_ \ [mn_j_ RBUF jZkiheZ]Zy bo \ ihjy^d_ \hajZklZgby ghf_jh\ ijhp_kkh\

GZ ijhp_kk_ ROOT kms_kl\_ggufb y\eyxlky agZq_gby \k_o iZjZf_ljh\ Z gZ hklZevguo ijhp_kkZo — lhevdh agZq_gby iZjZf_ljh\ SBUF, SCOUNT, STYPE, ROOT b COMM AgZq_gby iZjZf_ljh\ ROOT b COMM ^he`gu [ulv h^bgZdh\ufb m \k_o ijhp_kkh\ IZjZf_lj RCOUNT m ijhp_kkZ ROOT h[hagZqZ_l qbkeh we_f_g- lh\ lbiZ RTYPE ijbgbfZ_fuo g_ hl \k_o ijhp_kkh\ \ kmff_ Z hl dZ`^h]h ijhp_kkZ

Ke_^mxsZy ko_fZ beexkljbjm_l ^_ckl\b_ ijhp_^mju MPI_GATHER.

GZijbf_j ^ey lh]h qlh[u ijhp_kk 2 kh[jZe \ fZkkb\ rbuf ih 10 p_ehqbke_g- guo we_f_glh\ fZkkb\h\ buf kh \k_o ijhp_kkh\ ijbeh`_gby gm`gh qlh[u \h \k_o ijhp_kkZo \klj_lbeky ke_^mxsbc \uah\

	call MPI_GATHER(buf, 10, MPI_INTEGER,
&	rbuf, 10, MPI_INTEGER,
&	2, MPI_COMM_WORLD, ierr)

MPI_GATHERV(SBUF, SCOUNT, STYPE, RBUF, RCOUNTS, DISPLS, RTYPE, ROOT, COMM, IERR)

<type> SBUF(*), RBUF(*)

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INTEGER SCOUNT, STYPE, RCOUNTS(*), DISPLS(*), RTYPE, ROOT, COMM, IERR

K[hjdZ jZaebqgh]h dhebq_kl\Z ^Zgguo ba fZkkb\h\ SBUF Ihjy^hd jZkiheh- `_gby ^Zgguo \ j_amevlbjmxs_f [mn_j_ RBUF aZ^Z_l fZkkb\ DISPLS.

RCOUNTS – p_ehqbke_gguc fZkkb\ kh^_j`Zsbc dhebq_kl\h we_f_glh\ i_j_- ^Z\Z_fuo hl dZ`^h]h ijhp_kkZ bg^_dk jZ\_g jZg]m ihkueZxs_]h ijhp_kkZ jZaf_j fZkkb\Z jZ\_g qbkem ijhp_kkh\ \ dhffmgbdZlhj_ COMM).

DISPLS – p_ehqbke_gguc fZkkb\ kh^_j`Zsbc kf_s_gby hlghkbl_evgh gZ- qZeZ fZkkb\Z RBUF bg^_dk jZ\_g jZg]m ihkueZxs_]h ijhp_kkZ jZaf_j fZkkb\Z jZ\_g qbkem ijhp_kkh\ \ dhffmgbdZlhj_ COMM).

>Zggu_ ihkeZggu_ ijhp_kkhf J-1 jZaf_sZxlky \ J-hf [ehd_ [mn_jZ RBUF gZ ijhp_kk_ ROOT dhlhjuc gZqbgZ_lky kh kf_s_gb_f \ DISPLS(J) we_f_glh\ lbiZ RTYPE k gZqZeZ [mn_jZ

MPI_SCATTER(SBUF, SCOUNT, STYPE, RBUF, RCOUNT, RTYPE, ROOT, COMM, IERR)

<type> SBUF(*), RBUF(*)

INTEGER SCOUNT, STYPE, RCOUNT, RTYPE, ROOT, COMM, IERR

Ijhp_^mjZ MPI_SCATTER ih k\h_fm ^_ckl\bx y\ey_lky h[jZlghc d MPI_GATHER HgZ hkms_kl\ey_l jZkkuedm ih SCOUNT we_f_glh\ ^Zgguo lbiZ STYPE ba fZkkb\Z SBUF ijhp_kkZ ROOT \ fZkkb\u RBUF \k_o ijhp_kkh\ dhffm- gbdZlhjZ COMM \dexqZy kZf ijhp_kk ROOT Fh`gh kqblZlv qlh fZkkb\ SBUF ^_eblky gZ jZ\gu_ qZklb ih qbkem ijhp_kkh\ dZ`^Zy ba dhlhjuo khklhbl ba SCOUNT we_f_glh\ lbiZ STYPE ihke_ q_]h I-y qZklv ihkueZ_lky I-1)-fm ijhp_kkm

GZ ijhp_kk_ ROOT kms_kl\_ggufb y\eyxlky agZq_gby \k_o iZjZf_ljh\ Z gZ \k_o hklZevguo ijhp_kkZo — lhevdh agZq_gby iZjZf_ljh\ RBUF, RCOUNT, RTYPE, SOURCE b COMM AgZq_gby iZjZf_ljh\ SOURCE b COMM ^he`gu [ulv h^bgZdh\ufb m \k_o ijhp_kkh\

Ke_^mxsZy ko_fZ beexkljbjm_l ^_ckl\b_ ijhp_^mju MPI_SCATTER.

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