I had a similar problem with OOM errors on a RH 3 box running an smp kernel, with 9i RAC DB's Every week I had DB's crashing with ORA-27504: IPC error creating OSD context, and other OOM errors Setting the following kernel parameter helped for while, then every few weeks my load would shoot through the roof 150+, then die vm.vm-defragment = 1000 Using the hugemem kernel has fixed the problem here, for now at least. I'm migrating to 64 now. and since your already on hugemem, any patches will only be bandaid solutions. The only way you truly fix the problem though is to migrate to 64bit David Hill Oracle DBA -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Niall Litchfield Sent: Monday, February 11, 2008 5:20 AM To: tim@xxxxxxxxx Cc: Oracle List Subject: Re: Linux LowMem errors Not that MTU! There's an Oracle patch which has the following effect change skgxp MTU from 32k to 16k What seems to be happening is that Oracle requests 32k chunks of memory from the OS for (I think) IPC packets. The bug description suggests that Linux is somewhat prone to low memory fragmentation and isn't able to allocate the memory. On Feb 10, 2008 3:59 PM, Tim Gorman <tim@xxxxxxxxx> wrote: MTU of 32768 sounds interesting -- usually it is set to 1500, occasionally 9000. Not sure if this is significant, and I could be misinterpreting "requirement" for "setting" or some such, but I thought worth noting... Niall Litchfield wrote: We've recently updated some of our RH database servers to kernel 2.4.21-53ELHugemem and have experienced problems with the databases and ASM instances crashing and huge numbers (like 80,000) yesterday on one box of core dumps. The crashes did not occur immediately after the kernel update, but that is AFAIK the only significant recent change. The head of the trace reads SKGXPVFYMMTU: Could not create context which satisfies the minimum MTU requirement of 32768 bytes kgefec: fatal error 0 *** 2008-02-09 07:29:39.767 ksedmp: internal or fatal error ORA-00603: ORACLE server session terminated by fatal error ORA-27504: IPC error creating OSD context ORA-27300: OS system dependent operation:sendmsg failed with status: 12 ORA-27301: OS failure message: Cannot allocate memory ORA-27302: failure occurred at: sskgxpsnd1 which looks significantly like the issue addressed in Note 419871.1. to me. Has anyone else come across these issues? -- Niall Litchfield Oracle DBA http://www.orawin.info <http://www.orawin.info/> -- Niall Litchfield Oracle DBA http://www.orawin.info __________________________________ Nous avons déménagé! Notre nouvelle adresse est le : We've moved! Our new address is: 8300 Décarie Boulevard Montréal, (Québec) H4P 2P5 CONFIDENTIALITY NOTICE This message contains confidential information intended only for the use of the individual or entity named as recipient. Any dissemination, distribution or copying of this communication by anyone other than the intended recipient is strictly prohibited. If you have received this message in error, please immediately notify us and delete your copy. Thank you. AVIS DE CONFIDENTIALITÉ Les informations contenues aux présentes sont de nature privilégiée et confidentielle. Elles ne peuvent être utilisées que par la personne ou l'entité dont le nom paraît comme destinataire. Si le lecteur du présent message n'est pas le destinataire prévu, il est par les présentes prié de noter qu'il est strictement interdit de divulguer, de distribuer ou de copier ce message. Si ce message vous a été transmis par mégarde, veuillez nous en aviser immédiatement et supprimer votre copie. Merci.