Re: Storing Solr Index on NFS
Hi Walter; You said: It is not safe to share Solr index files between two Solr servers. Why do you think like that? 2013/4/16 Tim Vaillancourt t...@elementspace.com If centralization of storage is your goal by choosing NFS, iSCSI works reasonably well with SOLR indexes, although good local-storage will always be the overall winner. I noticed a near 5% degredation in overall search performance (casual testing, nothing scientific) when moving a 40-50GB indexes to iSCSI (10GBe network) from a 4x7200rpm RAID 10 local SATA disk setup. Tim On 15/04/13 09:59 AM, Walter Underwood wrote: Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwoodwunder@wunderwood.** org wun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org -- Walter Underwood wun...@wunderwood.org
Re: Storing Solr Index on NFS
Furkan, see this post. http://grokbase.com/t/lucene/solr-user/117t1eswyk/multiple-solr-servers-and-a-shared-index-again Cumprimentos -- Yago Riveiro Sent with Sparrow (http://www.sparrowmailapp.com/?sig) On Tuesday, April 16, 2013 at 12:15 PM, Furkan KAMACI wrote: Hi Walter; You said: It is not safe to share Solr index files between two Solr servers. Why do you think like that? 2013/4/16 Tim Vaillancourt t...@elementspace.com (mailto:t...@elementspace.com) If centralization of storage is your goal by choosing NFS, iSCSI works reasonably well with SOLR indexes, although good local-storage will always be the overall winner. I noticed a near 5% degredation in overall search performance (casual testing, nothing scientific) when moving a 40-50GB indexes to iSCSI (10GBe network) from a 4x7200rpm RAID 10 local SATA disk setup. Tim On 15/04/13 09:59 AM, Walter Underwood wrote: Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwoodwunder@wunderwood.** org wun...@wunderwood.org (mailto:wun...@wunderwood.org)wrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org (mailto:wun...@wunderwood.org) -- Walter Underwood wun...@wunderwood.org (mailto:wun...@wunderwood.org)
Re: Storing Solr Index on NFS
Yesterday, we spent 1 hour with a client looking at their cluster's performance metrics SPM, their indexing logs, etc. trying to figure out why some indexing was slower than it should have been. We traced issues to network hickups, to VMs that would move from host to host, etc. Really fancy and powerful system in terms of hardware resources, but in the end a bit too far from just locally attached HDD or SDD that would not have issues like the ones we found. I'd stay away from NFS for the same reason - it's another moving part on the other side of the network. Otis -- Solr ElasticSearch Support http://sematext.com/ On Tue, Apr 16, 2013 at 7:15 AM, Furkan KAMACI furkankam...@gmail.com wrote: Hi Walter; You said: It is not safe to share Solr index files between two Solr servers. Why do you think like that? 2013/4/16 Tim Vaillancourt t...@elementspace.com If centralization of storage is your goal by choosing NFS, iSCSI works reasonably well with SOLR indexes, although good local-storage will always be the overall winner. I noticed a near 5% degredation in overall search performance (casual testing, nothing scientific) when moving a 40-50GB indexes to iSCSI (10GBe network) from a 4x7200rpm RAID 10 local SATA disk setup. Tim On 15/04/13 09:59 AM, Walter Underwood wrote: Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwoodwunder@wunderwood.** org wun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org -- Walter Underwood wun...@wunderwood.org
Re: Storing Solr Index on NFS
I don't want to bother but I try to understand that part: When yo perform a commit in solr you have (for an instant) two versions of the index. The commit produces new segments (with new documents, new deletions, etc). After creating these new segments a new index searcher is created and its caches begin to autowarm. At this point the old index searcher that you were using is still active receiving requests. After the new index searcher finishes loading and autowarming the old searcher is discarded. So does it mean that when I have multiple Solr servers and a shared index, I should synchronize the caches at that different machines RAMs? 2013/4/17 Otis Gospodnetic otis.gospodne...@gmail.com Yesterday, we spent 1 hour with a client looking at their cluster's performance metrics SPM, their indexing logs, etc. trying to figure out why some indexing was slower than it should have been. We traced issues to network hickups, to VMs that would move from host to host, etc. Really fancy and powerful system in terms of hardware resources, but in the end a bit too far from just locally attached HDD or SDD that would not have issues like the ones we found. I'd stay away from NFS for the same reason - it's another moving part on the other side of the network. Otis -- Solr ElasticSearch Support http://sematext.com/ On Tue, Apr 16, 2013 at 7:15 AM, Furkan KAMACI furkankam...@gmail.com wrote: Hi Walter; You said: It is not safe to share Solr index files between two Solr servers. Why do you think like that? 2013/4/16 Tim Vaillancourt t...@elementspace.com If centralization of storage is your goal by choosing NFS, iSCSI works reasonably well with SOLR indexes, although good local-storage will always be the overall winner. I noticed a near 5% degredation in overall search performance (casual testing, nothing scientific) when moving a 40-50GB indexes to iSCSI (10GBe network) from a 4x7200rpm RAID 10 local SATA disk setup. Tim On 15/04/13 09:59 AM, Walter Underwood wrote: Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwoodwunder@wunderwood. ** org wun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org -- Walter Underwood wun...@wunderwood.org
Storing Solr Index on NFS
Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? Thanks, Saqib
Re: Storing Solr Index on NFS
On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org
Re: Storing Solr Index on NFS
Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwood wun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org
Re: Storing Solr Index on NFS
Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwood wun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org -- Walter Underwood wun...@wunderwood.org
Re: Storing Solr Index on NFS
If centralization of storage is your goal by choosing NFS, iSCSI works reasonably well with SOLR indexes, although good local-storage will always be the overall winner. I noticed a near 5% degredation in overall search performance (casual testing, nothing scientific) when moving a 40-50GB indexes to iSCSI (10GBe network) from a 4x7200rpm RAID 10 local SATA disk setup. Tim On 15/04/13 09:59 AM, Walter Underwood wrote: Solr 4.2 does have field compression which makes smaller indexes. That will reduce the amount of network traffic. That probably does not help much, because I think the latency of NFS is what causes problems. wunder On Apr 15, 2013, at 9:52 AM, Ali, Saqib wrote: Hello Walter, Thanks for the response. That has been my experience in the past as well. But I was wondering if there new are things in Solr 4 and NFS 4.1 that make the storing of indexes on a NFS mount feasible. Thanks, Saqib On Mon, Apr 15, 2013 at 9:47 AM, Walter Underwoodwun...@wunderwood.orgwrote: On Apr 15, 2013, at 9:40 AM, Ali, Saqib wrote: Greetings, Are there any issues with storing Solr Indexes on a NFS share? Also any recommendations for using NFS for Solr indexes? I recommend that you do not put Solr indexes on NFS. It can be very slow, I measured indexing as 100X slower on NFS a few years ago. It is not safe to share Solr index files between two Solr servers, so there is no benefit to NFS. wunder -- Walter Underwood wun...@wunderwood.org -- Walter Underwood wun...@wunderwood.org
