Hi Ketan, Just adding others, as well. Yeah. I was aware of this, before I had gone for this option. I am using EXT3 only. But still it gives me error.
I am aware of Memory alignment issues too. But what more can I do for a memory malloc'd from RAM. I have CMEM allocations to try. But I will keep that as the last option, as it doesn't talk of portability if I have to trust CMEM. Regards, Gopal Sukumar. ketan deshpande wrote: Hello Gopal, Whats the filesystem are you are using on the SD card?? VFAT? or EXT2? As far as i know; O_DIRECT i.e. 'disabling File System buffer cache' is not supported by those File Systems so you may have to try something like EXT3. I guess EXT3 supports disabling of File System buffer caching. regards, -Ketan ________________________________ From: Gopal Sukumar <[email protected]><mailto:[email protected]> To: DaVinciMailingList <[email protected]><mailto:[email protected]> Cc: [email protected]<mailto:[email protected]> Sent: Friday, 6 February, 2009 11:39:52 PM Subject: Writing streaming content on to SD Flash Hi all, I am writing an application that dumps A/V data into the SD Flash card in the order of around 1.5 MB/sec. I am trying to use O_DIRECT flag when I open a file into which the A/V data goes. I am using this flag because I want to shutdown buffer-caching during IO as buffer-cached IO takes longer time. But it gives perror as "Invalid argument" during writing. Please let me know, what I am missing here. Also please let me know, if you have other suggestions for faster and direct write to disk, instead of having to assume that the kernel would have done it. I am sure that many of you would have such requirements. It would be great to know the possible solutions to tackle the issue. Regards, Gopal Sukumar. DISCLAIMER: This message (including attachment if any) is confidential and may be privileged. If you have received this message by mistake please notify the sender by return e-mail and delete this message from your system. Any unauthorized use or dissemination of this message in whole or in part is strictly prohibited. E-mail may contain viruses. Before opening attachments please check them for viruses and defects. While MindTree Limited (MindTree) has put in place checks to minimize the risks, MindTree will not be responsible for any viruses or defects or any forwarded attachments emanating either from within MindTree or outside. Please note that e-mails are susceptible to change and MindTree shall not be liable for any improper, untimely or incomplete transmission. MindTree reserves the right to monitor and review the content of all messages sent to or from MindTree e-mail address. Messages sent to or from this e-mail address may be stored on the MindTree e-mail system or else where. ________________________________ http://www.mindtree.com/email/disclaimer.html ________________________________ Unlimited freedom, unlimited storage. Get it now<http://in.rd.yahoo.com/tagline_mail_2/*http://help.yahoo.com/l/in/yahoo/mail/yahoomail/tools/tools-08.html/> DISCLAIMER: This message (including attachment if any) is confidential and may be privileged. If you have received this message by mistake please notify the sender by return e-mail and delete this message from your system. Any unauthorized use or dissemination of this message in whole or in part is strictly prohibited. E-mail may contain viruses. Before opening attachments please check them for viruses and defects. While MindTree Limited (MindTree) has put in place checks to minimize the risks, MindTree will not be responsible for any viruses or defects or any forwarded attachments emanating either from within MindTree or outside. Please note that e-mails are susceptible to change and MindTree shall not be liable for any improper, untimely or incomplete transmission. MindTree reserves the right to monitor and review the content of all messages sent to or from MindTree e-mail address. Messages sent to or from this e-mail address may be stored on the MindTree e-mail system or else where. ________________________________ http://www.mindtree.com/email/disclaimer.html
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