ESS nodes have cache, but what matters most for this type of workloads is to have a very large metadata cache, this resides on the CES node for SMB/NFS workloads. so if you know that your client will use this 300k directory a lot you want to have a very large maxfilestocache setting on this nodes. alternative solution is to install a LROC device and configure a larger statcache, this helps especially if you have multiple larger directories and want to cache as many as possible from all of them. make sure you have enough tokenmanager and memory on them if you have multiple CES nodes and they all will have high settings.
sven ------------------------------------------ Sven Oehme Scalable Storage Research email: [email protected] Phone: +1 (408) 824-8904 IBM Almaden Research Lab ------------------------------------------ From: Mark Bush <[email protected]> To: gpfsug main discussion list <[email protected]> Date: 05/09/2017 05:25 PM Subject: [gpfsug-discuss] CES and Directory list populating very slowly Sent by: [email protected] I have a customer who is struggling (they already have a PMR open and it’s being actively worked on now). I’m simply seeking understanding of potential places to look. They have an ESS with a few CES nodes in front. Clients connect via SMB to the CES nodes. One fileset has about 300k smallish files in it and when the client opens a windows browser it takes around 30mins to finish populating the files in this SMB share. Here’s where my confusion is. When a client connects to a CES node this is all the job of the CES and it’s protocol services to handle, so in this case CTDB/Samba. But the flow of this is where maybe I’m a little fuzzy. Obviously the CES nodes act as clients to the NSD (IO/nodes in ESS land) servers. So, the data really doesn’t exist on the protocol node but passes things off to the NSD server for regular IO processing. Does the CES node do some type of caching? I’ve heard talk of LROC on CES nodes potentially but I’m curious if all of this is already being stored in the pagepool? What could cause a mostly metadata related simple directory lookup take what seems to the customer a long time for a couple hundred thousand files? Mark This message (including any attachments) is intended only for the use of the individual or entity to which it is addressed and may contain information that is non-public, proprietary, privileged, confidential, and exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any use, dissemination, distribution, or copying of this communication is strictly prohibited. This message may be viewed by parties at Sirius Computer Solutions other than those named in the message header. This message does not contain an official representation of Sirius Computer Solutions. If you have received this communication in error, notify Sirius Computer Solutions immediately and (i) destroy this message if a facsimile or (ii) delete this message immediately if this is an electronic communication. Thank you. Sirius Computer Solutions _______________________________________________ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
_______________________________________________ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
