From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ciao.gmane.io (ciao.gmane.io [116.202.254.214]) by sourceware.org (Postfix) with ESMTPS id 2B3613858D35 for ; Fri, 25 Feb 2022 20:44:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 2B3613858D35 Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1nNhST-0009Jk-HZ for fortran@gcc.gnu.org; Fri, 25 Feb 2022 21:44:57 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: fortran@gcc.gnu.org From: Harald Anlauf Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Date: Fri, 25 Feb 2022 21:44:53 +0100 Message-ID: <9546ace7-cab6-9115-e83a-2a4eecab191f@gmx.de> References: <2916ad84-bfbe-757b-290e-61d9c5805367@gmx.de> <99fe8038e55242b1bc4e7792ff0d7777@gsi.de> <45776b22-8587-597c-c2d1-93df2c8cfdbb@codesourcery.com> <5a95ec72581b4c8fb59e81fdb93e4991@gsi.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Cc: Tobias Burnus , "fortran@gcc.gnu.org" Content-Language: en-US In-Reply-To: X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, NICE_REPLY_A, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: fortran@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Fortran mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Feb 2022 20:45:00 -0000 Hi Denis, > export GFORTRAN_UNFORMATTED_BUFFER_SIZE=10000 > export GFORTRAN_FORMATTED_BUFFER_SIZE=10000 > export GFORTRAN_UNBUFFERED_ALL=n > > From the output log indeed i got the correct env. variable as i set: > > > GFORTRAN_FORMATTED_BUFFER_SIZE=10000 > > > But from strace output i got always > > >>>>>>>>>>>>>>>>>>>>>>> > > write(3, "\0\0\0\0\0\0\10@\0\0\0\340\314\314\10@\0\0\0\240\231\231\t@\0\0\0`ff\n@"..., 8192) = 8192 > write(3, "\0\0\0@33\v@\0\0\0\0\0\0\f@\0\0\0\340\314\314\f@\0\0\0\240\231\231\r@"..., 8192) = 8192 > write(3, "\0\0\0`ff\16@\0\0\0@33\17@\0\0\0\0\0\0\20@\0\0\0`ff\20@"..., 8192) = 8192 > write(3, "\0\0\0\340\314\314\20@\0\0\0@33\21@\0\0\0\240\231\231\21@\0\0\0\0\0\0\22@"..., 8192) = 8192 > write(3, "\0\0\0`ff\22@\0\0\0\340\314\314\22@\0\0\0@33\23@\0\0\0\240\231\231\23@"..., 8192) = 8192 > write(3, "\0\0\0\0\0\0\24@\0\0\0`ff\24@\0\0\0\340\314\314\24@\0\0\0@33\25@"..., 8192) = 8192 > ..... >>>>>>>>>>>>>>>>>>> > Showing the fixed that still a 8kiB buffer size is effectively ude in I/O... did you ever think of trying other values than 10000? On my Linux laptop, buffering is done in multiples of 2k. If I set GFORTRAN_UNFORMATTED_BUFFER_SIZE=14000, I get writes in sizes of 12288. Which is likely more efficient than asking for exactly 14000. Cheers, Harald From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net (mout.gmx.net [212.227.17.22]) by sourceware.org (Postfix) with ESMTPS id 487053858C27 for ; Fri, 25 Feb 2022 20:45:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 487053858C27 X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [192.168.178.29] ([93.207.80.186]) by mail.gmx.net (mrgmx104 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MZTmY-1nlMK82pyo-00WZQ6; Fri, 25 Feb 2022 21:44:54 +0100 Message-ID: <9546ace7-cab6-9115-e83a-2a4eecab191f@gmx.de> Date: Fri, 25 Feb 2022 21:44:53 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: Problem setting buffer size for gfortran ( v 11.2) Content-Language: en-US To: "Bertini, Denis Dr." Cc: Tobias Burnus , "fortran@gcc.gnu.org" Newsgroups: gmane.comp.gcc.fortran References: <2916ad84-bfbe-757b-290e-61d9c5805367@gmx.de> <99fe8038e55242b1bc4e7792ff0d7777@gsi.de> <45776b22-8587-597c-c2d1-93df2c8cfdbb@codesourcery.com> <5a95ec72581b4c8fb59e81fdb93e4991@gsi.de> From: Harald Anlauf In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:+ATMIIOuJ9348LuRW6KiIa/J2bjqSQ11eAsSQrrjYp5ysWrtRxz PojigLjN/R6QNofg9U6x3nTH6LMq3wCDkgwJhXAsuLZNuQXM84dwwnoiiPR3dktP3kM19Qy GWZomA9Qcf1NyGB21Bfs5ueqH8roHSbhjalWtInkwTq+Vi8wezpCvVHWiloQmClWvzlsF+B seO/TQSh6FgZiHZgiZs9w== X-UI-Out-Filterresults: notjunk:1;V03:K0:CLMw96PirlU=:siB9UuvvfVa5Zc1LLofmbN VIKSS7sR/9Qfe5rgYe9W2S+0VLlbQ47hiowFwR4tEF2Rv3gCZyMfj5g/3lzhksKBzwbku5YAq lJA+IM3xFOMJOqECFa1ZK9oIB4yz2Gth4EdhgRmUQie3fKzUIDsOAYb5XF+ZLyCkhDpbM0kXu PZIl5DxfqC30ZpH+KCEz3olGxwi4UzbNB7csil+EeLIxbD+ewoAII8YQhf4zF9ne/4pJFrUBY BJV4j7VCcvQQZ8ESDUh/ln6+6rtPQ1ksYekyMitVscFN60xD9UgWcew8LzPGrAbNMC1BfdK2z LhjZ6TeLkOhNLiuZKSC975+rwTTFZWVFYFa7ACoS8tUTfFOe5enS330GWW0OAWzuVsEGw5h6X a0K6ozpYhlPPFC+HonFSF8GigEe+Xemt72xPw1D18Vc7Wuw4ijPj+yWK58iF0HgTKZ6/agbrY 60S2XfJzKYbSyoRHTqZGelsFhDFixPrTWlD2NckFFgtNWmCfLvNNd5ojJUt0NSji8GixRw6Jb 5hHRqla6QVCTMROJowBwwn48LvuYkYQR9vB7eYt5fXlw0aNFoipoqMVE2Yyi2sSi2mXk3YVAh KkvuZQ5ZYIsPCGT+H1Y1MMTFQ/fgc4PzaQzEwYTkuWzcluO1f4JPmHtVcg5SIfCS/IEg6cenE ksDjwnyv6NVkAZNS3gmUNU8aDf3gDIYOelAabEkQ2x3uvHtmIgleg3pyLT0ZSVolFSN27igza tzdy87yMAxrPxHg8pFwOMjfGb6GQJZhng5lDXvzgs4aPVa5Xlg/QZGoF9wgVvV7zn994sLwtA ZWISMkph8UkK5Y1L7vtzSEmCjdrgch9MDbGV7aTJq7mvcmMpxQ6ef+qL77uuMlpKU7RVmgI4C skHG926ZmoFjzJ2rnjvolGmfXIhN0+UnBQnh7ip8ydywhFVqY71Nczjr0su8tH0FJph7mgY/v BygwGwI5iehCtZXv1udz1wpgTVvm2axAtGZxxUqQgx8Rl0uUmBMo+z4eI9Guyvd0ztoSX6glW N5rcXx/U+vE1r5P8NtvyBUAj/caHfSKQuHmGG4aPK9T5iutZp3/Ffc/K5DvkKRq7l8bETysro E5o4F8AiruBsNc= X-Spam-Status: No, score=-4.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, FREEMAIL_FROM, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: fortran@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Fortran mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Feb 2022 20:45:01 -0000 Message-ID: <20220225204453.KJaqRCegIVmA33bZw3BYAZcKPhl3CvR_MAdPzRYCRnY@z> Hi Denis, > export GFORTRAN_UNFORMATTED_BUFFER_SIZE=3D10000 > export GFORTRAN_FORMATTED_BUFFER_SIZE=3D10000 > export GFORTRAN_UNBUFFERED_ALL=3Dn > > From the output log indeed i got the correct env. variable as i set: > > > GFORTRAN_FORMATTED_BUFFER_SIZE=3D10000 > > > But from strace output i got always > > >>>>>>>>>>>>>>>>>>>>>>> > > write(3, "\0\0\0\0\0\0\10@\0\0\0\340\314\314\10@\0\0\0\240\231\231\t@\0\= 0\0`ff\n@"..., 8192) =3D 8192 > write(3, "\0\0\0@33\v@\0\0\0\0\0\0\f@\0\0\0\340\314\314\f@\0\0\0\240\231= \231\r@"..., 8192) =3D 8192 > write(3, "\0\0\0`ff\16@\0\0\0@33\17@\0\0\0\0\0\0\20@\0\0\0`ff\20@"..., 8= 192) =3D 8192 > write(3, "\0\0\0\340\314\314\20@\0\0\0@33\21@\0\0\0\240\231\231\21@\0\0\= 0\0\0\0\22@"..., 8192) =3D 8192 > write(3, "\0\0\0`ff\22@\0\0\0\340\314\314\22@\0\0\0@33\23@\0\0\0\240\231= \231\23@"..., 8192) =3D 8192 > write(3, "\0\0\0\0\0\0\24@\0\0\0`ff\24@\0\0\0\340\314\314\24@\0\0\0@33\2= 5@"..., 8192) =3D 8192 > ..... >>>>>>>>>>>>>>>>>>> > Showing the fixed that still a 8kiB buffer size is effectively ude in I= /O... did you ever think of trying other values than 10000? On my Linux laptop, buffering is done in multiples of 2k. If I set GFORTRAN_UNFORMATTED_BUFFER_SIZE=3D14000, I get writes in sizes of 12288. Which is likely more efficient than asking for exactly 14000. Cheers, Harald