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Jean-Marc Spaggiari
2013-01-04, 15:24
Anton Lyska
2013-01-04, 15:32
Damien Hardy
2013-01-04, 15:35
Jean-Marc Spaggiari
2013-01-04, 19:58
Adrien Mogenet
2013-01-04, 20:17
Mohamed Ibrahim
2013-01-04, 21:04
Jean-Marc Spaggiari
2013-01-05, 13:29
Mohamed Ibrahim
2013-01-05, 14:07
Asaf Mesika
2013-01-06, 20:27
Jean-Marc Spaggiari
2013-01-07, 02:14
Jean-Marc Spaggiari
2013-01-04, 20:28
Bryan Beaudreault
2013-01-04, 20:45
Jean-Marc Spaggiari
2013-01-04, 20:54
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Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-04, 15:24
Hi,
What's the fastest way to know if a row exist? Today I'm doing that: Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); Result entry_exist = table_entry.get(get_entry_exist); But should this be faster? Get get_entry_exist = new Get(key); Result entry_exist = table_entry.get(get_entry_exist); There is only one CF and one C on my table. Or is there an even faster way? Also, is there a way to make that even faster? I think BloomFilters can help, right? Thanks, JM +
Jean-Marc Spaggiari 2013-01-04, 15:24
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Re: Fastest way to find is a row exist?Anton Lyska 2013-01-04, 15:32
Hi,
using KeyOnlyFilter will prevent sending value via netrwork 04.01.2013 17:24, Jean-Marc Spaggiari пишет: > Hi, > > What's the fastest way to know if a row exist? > > Today I'm doing that: > > Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); > Result entry_exist = table_entry.get(get_entry_exist); > > But should this be faster? > Get get_entry_exist = new Get(key); > Result entry_exist = table_entry.get(get_entry_exist); > > There is only one CF and one C on my table. > > Or is there an even faster way? > > Also, is there a way to make that even faster? I think BloomFilters > can help, right? > > Thanks, > > JM > +
Anton Lyska 2013-01-04, 15:32
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Re: Fastest way to find is a row exist?Damien Hardy 2013-01-04, 15:35
Hello Jean-Marc,
BloomFilters are just designed for that. But they say if a row doesn't exist with a ash of the key (not the oposit, 2 rowkeys could have the same ash result). If you want to be sure the rowkey exists you have to search for it in the HFile ( the whole mechanism is transparent with the get() ). Their is also an KeOnlyFilter http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html preventing from getting the whole columns of the existing key as return (which could be heavy). Cheers, -- Damien 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > Hi, > > What's the fastest way to know if a row exist? > > Today I'm doing that: > > Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); > Result entry_exist = table_entry.get(get_entry_exist); > > But should this be faster? > Get get_entry_exist = new Get(key); > Result entry_exist = table_entry.get(get_entry_exist); > > There is only one CF and one C on my table. > > Or is there an even faster way? > > Also, is there a way to make that even faster? I think BloomFilters > can help, right? > > Thanks, > > JM > +
Damien Hardy 2013-01-04, 15:35
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Re: Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-04, 19:58
Is KeyOnlyFilter using the BloomFilters too?
Here is, with more details, what I'm doing. Few questions. - Can I create one single KeyOnlyFilter and give the same filter to all the gets? - Will bloom filters benefit in such scenario? My key is small. Let's say average 128 bytes. The goal here is to check about 500 entries at a time to validate if they already exist or not. In my MR, I'm starting when I have more than 100K lines to handle, and each line car have up to 1K entries. So it can result up to 100M gets... Job took initially 500 minutes to complete. I have added few pretty good nodes and it's not taking less than 300 minutes. But I would like to get under 100 minutes if I can... Thanks, JM Vector<Get> gets_entry_exist = new Vector<Get>(); for (Entry entry : entries.getEntries()) { Get entry_exist = new Get(entry.toKey()); entry_exist.setFilter(new KeyOnlyFilter()); gets_entry_exist.add(entry_exist); } Result[] result_entry_exist = table_entry.get(gets_entry_exist); int index = 0; for (Entry entry : entries.getEntries()) { boolean isEmpty = result_entry_exist[index++].isEmpty(); if (isEmpty) { // Process here } } { 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: > Hello Jean-Marc, > > BloomFilters are just designed for that. > > But they say if a row doesn't exist with a ash of the key (not the oposit, > 2 rowkeys could have the same ash result). > > If you want to be sure the rowkey exists you have to search for it in the > HFile ( the whole mechanism is transparent with the get() ). > > Their is also an KeOnlyFilter > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html > preventing from getting the whole columns of the existing key as return > (which could be heavy). > > Cheers, > > -- > Damien > > > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > >> Hi, >> >> What's the fastest way to know if a row exist? >> >> Today I'm doing that: >> >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); >> Result entry_exist = table_entry.get(get_entry_exist); >> >> But should this be faster? >> Get get_entry_exist = new Get(key); >> Result entry_exist = table_entry.get(get_entry_exist); >> >> There is only one CF and one C on my table. >> >> Or is there an even faster way? >> >> Also, is there a way to make that even faster? I think BloomFilters >> can help, right? >> >> Thanks, >> >> JM >> > +
Jean-Marc Spaggiari 2013-01-04, 19:58
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Re: Fastest way to find is a row exist?Adrien Mogenet 2013-01-04, 20:17
On every Get, BloomFilter is acting as a filter (!) on top of each HFile
and allows to check if a key is absent from the HFile. So yes, you will benefit from these filters. On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari <[EMAIL PROTECTED] > wrote: > Is KeyOnlyFilter using the BloomFilters too? > > Here is, with more details, what I'm doing. > > Few questions. > - Can I create one single KeyOnlyFilter and give the same filter to > all the gets? > - Will bloom filters benefit in such scenario? My key is small. Let's > say average 128 bytes. > > The goal here is to check about 500 entries at a time to validate if > they already exist or not. > > In my MR, I'm starting when I have more than 100K lines to handle, and > each line car have up to 1K entries. So it can result up to 100M > gets... Job took initially 500 minutes to complete. I have added few > pretty good nodes and it's not taking less than 300 minutes. But I > would like to get under 100 minutes if I can... > > Thanks, > > JM > > Vector<Get> gets_entry_exist = new Vector<Get>(); > for (Entry entry : entries.getEntries()) > { > Get entry_exist = new Get(entry.toKey()); > entry_exist.setFilter(new KeyOnlyFilter()); > gets_entry_exist.add(entry_exist); > } > > Result[] result_entry_exist = table_entry.get(gets_entry_exist); > > int index = 0; > for (Entry entry : entries.getEntries()) > { > boolean isEmpty = result_entry_exist[index++].isEmpty(); > if (isEmpty) > { > // Process here > } > } > { > > > 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: > > Hello Jean-Marc, > > > > BloomFilters are just designed for that. > > > > But they say if a row doesn't exist with a ash of the key (not the > oposit, > > 2 rowkeys could have the same ash result). > > > > If you want to be sure the rowkey exists you have to search for it in the > > HFile ( the whole mechanism is transparent with the get() ). > > > > Their is also an KeOnlyFilter > > > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html > > preventing from getting the whole columns of the existing key as return > > (which could be heavy). > > > > Cheers, > > > > -- > > Damien > > > > > > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > > > >> Hi, > >> > >> What's the fastest way to know if a row exist? > >> > >> Today I'm doing that: > >> > >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); > >> Result entry_exist = table_entry.get(get_entry_exist); > >> > >> But should this be faster? > >> Get get_entry_exist = new Get(key); > >> Result entry_exist = table_entry.get(get_entry_exist); > >> > >> There is only one CF and one C on my table. > >> > >> Or is there an even faster way? > >> > >> Also, is there a way to make that even faster? I think BloomFilters > >> can help, right? > >> > >> Thanks, > >> > >> JM > >> > > > -- Adrien Mogenet 06.59.16.64.22 http://www.mogenet.me +
Adrien Mogenet 2013-01-04, 20:17
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Re: Fastest way to find is a row exist?Mohamed Ibrahim 2013-01-04, 21:04
What about HTable.exists ??
http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#exists(org.apache.hadoop.hbase.client.Get) I think that should work if the Get has only the row key. Mohamed On Fri, Jan 4, 2013 at 3:17 PM, Adrien Mogenet <[EMAIL PROTECTED]>wrote: > On every Get, BloomFilter is acting as a filter (!) on top of each HFile > and allows to check if a key is absent from the HFile. So yes, you will > benefit from these filters. > > > On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari < > [EMAIL PROTECTED] > > wrote: > > > Is KeyOnlyFilter using the BloomFilters too? > > > > Here is, with more details, what I'm doing. > > > > Few questions. > > - Can I create one single KeyOnlyFilter and give the same filter to > > all the gets? > > - Will bloom filters benefit in such scenario? My key is small. Let's > > say average 128 bytes. > > > > The goal here is to check about 500 entries at a time to validate if > > they already exist or not. > > > > In my MR, I'm starting when I have more than 100K lines to handle, and > > each line car have up to 1K entries. So it can result up to 100M > > gets... Job took initially 500 minutes to complete. I have added few > > pretty good nodes and it's not taking less than 300 minutes. But I > > would like to get under 100 minutes if I can... > > > > Thanks, > > > > JM > > > > Vector<Get> gets_entry_exist = new Vector<Get>(); > > for (Entry entry : entries.getEntries()) > > { > > Get entry_exist = new Get(entry.toKey()); > > entry_exist.setFilter(new KeyOnlyFilter()); > > gets_entry_exist.add(entry_exist); > > } > > > > Result[] result_entry_exist = table_entry.get(gets_entry_exist); > > > > int index = 0; > > for (Entry entry : entries.getEntries()) > > { > > boolean isEmpty = result_entry_exist[index++].isEmpty(); > > if (isEmpty) > > { > > // Process here > > } > > } > > { > > > > > > 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: > > > Hello Jean-Marc, > > > > > > BloomFilters are just designed for that. > > > > > > But they say if a row doesn't exist with a ash of the key (not the > > oposit, > > > 2 rowkeys could have the same ash result). > > > > > > If you want to be sure the rowkey exists you have to search for it in > the > > > HFile ( the whole mechanism is transparent with the get() ). > > > > > > Their is also an KeOnlyFilter > > > > > > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html > > > preventing from getting the whole columns of the existing key as return > > > (which could be heavy). > > > > > > Cheers, > > > > > > -- > > > Damien > > > > > > > > > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > > > > > >> Hi, > > >> > > >> What's the fastest way to know if a row exist? > > >> > > >> Today I'm doing that: > > >> > > >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); > > >> Result entry_exist = table_entry.get(get_entry_exist); > > >> > > >> But should this be faster? > > >> Get get_entry_exist = new Get(key); > > >> Result entry_exist = table_entry.get(get_entry_exist); > > >> > > >> There is only one CF and one C on my table. > > >> > > >> Or is there an even faster way? > > >> > > >> Also, is there a way to make that even faster? I think BloomFilters > > >> can help, right? > > >> > > >> Thanks, > > >> > > >> JM > > >> > > > > > > > > > -- > Adrien Mogenet > 06.59.16.64.22 > http://www.mogenet.me > +
Mohamed Ibrahim 2013-01-04, 21:04
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Re: Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-05, 13:29
Hum, very interesting!
Now, what's the best option? Array of get which will retrieve more information? Or multiple HTable.exits one by one? The best will have been to have an array of gets passed to the exist... I will see how big it is to add that... JM 2013/1/4, Mohamed Ibrahim <[EMAIL PROTECTED]>: > What about HTable.exists ?? > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#exists(org.apache.hadoop.hbase.client.Get) > > I think that should work if the Get has only the row key. > > Mohamed > > > On Fri, Jan 4, 2013 at 3:17 PM, Adrien Mogenet > <[EMAIL PROTECTED]>wrote: > >> On every Get, BloomFilter is acting as a filter (!) on top of each HFile >> and allows to check if a key is absent from the HFile. So yes, you will >> benefit from these filters. >> >> >> On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari < >> [EMAIL PROTECTED] >> > wrote: >> >> > Is KeyOnlyFilter using the BloomFilters too? >> > >> > Here is, with more details, what I'm doing. >> > >> > Few questions. >> > - Can I create one single KeyOnlyFilter and give the same filter to >> > all the gets? >> > - Will bloom filters benefit in such scenario? My key is small. Let's >> > say average 128 bytes. >> > >> > The goal here is to check about 500 entries at a time to validate if >> > they already exist or not. >> > >> > In my MR, I'm starting when I have more than 100K lines to handle, and >> > each line car have up to 1K entries. So it can result up to 100M >> > gets... Job took initially 500 minutes to complete. I have added few >> > pretty good nodes and it's not taking less than 300 minutes. But I >> > would like to get under 100 minutes if I can... >> > >> > Thanks, >> > >> > JM >> > >> > Vector<Get> gets_entry_exist = new Vector<Get>(); >> > for (Entry entry : entries.getEntries()) >> > { >> > Get entry_exist = new Get(entry.toKey()); >> > entry_exist.setFilter(new KeyOnlyFilter()); >> > gets_entry_exist.add(entry_exist); >> > } >> > >> > Result[] result_entry_exist >> > table_entry.get(gets_entry_exist); >> > >> > int index = 0; >> > for (Entry entry : entries.getEntries()) >> > { >> > boolean isEmpty >> > result_entry_exist[index++].isEmpty(); >> > if (isEmpty) >> > { >> > // Process here >> > } >> > } >> > { >> > >> > >> > 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: >> > > Hello Jean-Marc, >> > > >> > > BloomFilters are just designed for that. >> > > >> > > But they say if a row doesn't exist with a ash of the key (not the >> > oposit, >> > > 2 rowkeys could have the same ash result). >> > > >> > > If you want to be sure the rowkey exists you have to search for it in >> the >> > > HFile ( the whole mechanism is transparent with the get() ). >> > > >> > > Their is also an KeOnlyFilter >> > > >> > >> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html >> > > preventing from getting the whole columns of the existing key as >> > > return >> > > (which could be heavy). >> > > >> > > Cheers, >> > > >> > > -- >> > > Damien >> > > >> > > >> > > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> >> > > >> > >> Hi, >> > >> >> > >> What's the fastest way to know if a row exist? >> > >> >> > >> Today I'm doing that: >> > >> >> > >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); >> > >> Result entry_exist = table_entry.get(get_entry_exist); >> > >> >> > >> But should this be faster? >> > >> Get get_entry_exist = new Get(key); >> > >> Result entry_exist = table_entry.get(get_entry_exist); >> > >> >> > >> There is only one CF and one C on my table. >> > >> >> > >> Or is there an even faster way? >> > >> >> > >> Also, is there a way to make that even faster? I think BloomFilters >> > >> can help, right? >> > >> >> > >> Thanks, +
Jean-Marc Spaggiari 2013-01-05, 13:29
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Re: Fastest way to find is a row exist?Mohamed Ibrahim 2013-01-05, 14:07
Sorry, I didn't notice your email about packing 500 operations before.
You might actually benefit from checking with a batch of Gets vs individual exists. Best, Mohamed On Sat, Jan 5, 2013 at 8:29 AM, Jean-Marc Spaggiari <[EMAIL PROTECTED] > wrote: > Hum, very interesting! > > Now, what's the best option? Array of get which will retrieve more > information? Or multiple HTable.exits one by one? > > The best will have been to have an array of gets passed to the > exist... I will see how big it is to add that... > > JM > > 2013/1/4, Mohamed Ibrahim <[EMAIL PROTECTED]>: > > What about HTable.exists ?? > > > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#exists(org.apache.hadoop.hbase.client.Get) > > > > I think that should work if the Get has only the row key. > > > > Mohamed > > > > > > On Fri, Jan 4, 2013 at 3:17 PM, Adrien Mogenet > > <[EMAIL PROTECTED]>wrote: > > > >> On every Get, BloomFilter is acting as a filter (!) on top of each HFile > >> and allows to check if a key is absent from the HFile. So yes, you will > >> benefit from these filters. > >> > >> > >> On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari < > >> [EMAIL PROTECTED] > >> > wrote: > >> > >> > Is KeyOnlyFilter using the BloomFilters too? > >> > > >> > Here is, with more details, what I'm doing. > >> > > >> > Few questions. > >> > - Can I create one single KeyOnlyFilter and give the same filter to > >> > all the gets? > >> > - Will bloom filters benefit in such scenario? My key is small. Let's > >> > say average 128 bytes. > >> > > >> > The goal here is to check about 500 entries at a time to validate if > >> > they already exist or not. > >> > > >> > In my MR, I'm starting when I have more than 100K lines to handle, and > >> > each line car have up to 1K entries. So it can result up to 100M > >> > gets... Job took initially 500 minutes to complete. I have added few > >> > pretty good nodes and it's not taking less than 300 minutes. But I > >> > would like to get under 100 minutes if I can... > >> > > >> > Thanks, > >> > > >> > JM > >> > > >> > Vector<Get> gets_entry_exist = new Vector<Get>(); > >> > for (Entry entry : entries.getEntries()) > >> > { > >> > Get entry_exist = new Get(entry.toKey()); > >> > entry_exist.setFilter(new KeyOnlyFilter()); > >> > gets_entry_exist.add(entry_exist); > >> > } > >> > > >> > Result[] result_entry_exist > >> > table_entry.get(gets_entry_exist); > >> > > >> > int index = 0; > >> > for (Entry entry : entries.getEntries()) > >> > { > >> > boolean isEmpty > >> > result_entry_exist[index++].isEmpty(); > >> > if (isEmpty) > >> > { > >> > // Process here > >> > } > >> > } > >> > { > >> > > >> > > >> > 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: > >> > > Hello Jean-Marc, > >> > > > >> > > BloomFilters are just designed for that. > >> > > > >> > > But they say if a row doesn't exist with a ash of the key (not the > >> > oposit, > >> > > 2 rowkeys could have the same ash result). > >> > > > >> > > If you want to be sure the rowkey exists you have to search for it > in > >> the > >> > > HFile ( the whole mechanism is transparent with the get() ). > >> > > > >> > > Their is also an KeOnlyFilter > >> > > > >> > > >> > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html > >> > > preventing from getting the whole columns of the existing key as > >> > > return > >> > > (which could be heavy). > >> > > > >> > > Cheers, > >> > > > >> > > -- > >> > > Damien > >> > > > >> > > > >> > > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > >> > > > >> > >> Hi, > >> > >> > >> > >> What's the fastest way to know if a row exist? > >> > >> > >> > >> Today I'm doing that: > >> > >> > >> > >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); +
Mohamed Ibrahim 2013-01-05, 14:07
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Re: Fastest way to find is a row exist?Asaf Mesika 2013-01-06, 20:27
Why not write your own filter class which you can initialize with a
set of keys to search for. The HTable on the client side will split the keys based on row keys so it will be sent to the right regions. There your filter can utilize SEEK_NEXT_USING_HINT Return Code to see efficiently on those set of key values This will ensure you do this search in one rpc call. Your filter can also transform the KeyValue so that only the row keys are returned Sent from my iPad On 6 בינו 2013, at 05:46, Mohamed Ibrahim <[EMAIL PROTECTED]> wrote: > Sorry, I didn't notice your email about packing 500 operations before. > > You might actually benefit from checking with a batch of Gets vs individual > exists. > > Best, > Mohamed > > > On Sat, Jan 5, 2013 at 8:29 AM, Jean-Marc Spaggiari <[EMAIL PROTECTED] >> wrote: > >> Hum, very interesting! >> >> Now, what's the best option? Array of get which will retrieve more >> information? Or multiple HTable.exits one by one? >> >> The best will have been to have an array of gets passed to the >> exist... I will see how big it is to add that... >> >> JM >> >> 2013/1/4, Mohamed Ibrahim <[EMAIL PROTECTED]>: >>> What about HTable.exists ?? >> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#exists(org.apache.hadoop.hbase.client.Get) >>> >>> I think that should work if the Get has only the row key. >>> >>> Mohamed >>> >>> >>> On Fri, Jan 4, 2013 at 3:17 PM, Adrien Mogenet >>> <[EMAIL PROTECTED]>wrote: >>> >>>> On every Get, BloomFilter is acting as a filter (!) on top of each HFile >>>> and allows to check if a key is absent from the HFile. So yes, you will >>>> benefit from these filters. >>>> >>>> >>>> On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari < >>>> [EMAIL PROTECTED] >>>>> wrote: >>>> >>>>> Is KeyOnlyFilter using the BloomFilters too? >>>>> >>>>> Here is, with more details, what I'm doing. >>>>> >>>>> Few questions. >>>>> - Can I create one single KeyOnlyFilter and give the same filter to >>>>> all the gets? >>>>> - Will bloom filters benefit in such scenario? My key is small. Let's >>>>> say average 128 bytes. >>>>> >>>>> The goal here is to check about 500 entries at a time to validate if >>>>> they already exist or not. >>>>> >>>>> In my MR, I'm starting when I have more than 100K lines to handle, and >>>>> each line car have up to 1K entries. So it can result up to 100M >>>>> gets... Job took initially 500 minutes to complete. I have added few >>>>> pretty good nodes and it's not taking less than 300 minutes. But I >>>>> would like to get under 100 minutes if I can... >>>>> >>>>> Thanks, >>>>> >>>>> JM >>>>> >>>>> Vector<Get> gets_entry_exist = new Vector<Get>(); >>>>> for (Entry entry : entries.getEntries()) >>>>> { >>>>> Get entry_exist = new Get(entry.toKey()); >>>>> entry_exist.setFilter(new KeyOnlyFilter()); >>>>> gets_entry_exist.add(entry_exist); >>>>> } >>>>> >>>>> Result[] result_entry_exist >>>>> table_entry.get(gets_entry_exist); >>>>> >>>>> int index = 0; >>>>> for (Entry entry : entries.getEntries()) >>>>> { >>>>> boolean isEmpty >>>>> result_entry_exist[index++].isEmpty(); >>>>> if (isEmpty) >>>>> { >>>>> // Process here >>>>> } >>>>> } >>>>> { >>>>> >>>>> >>>>> 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: >>>>>> Hello Jean-Marc, >>>>>> >>>>>> BloomFilters are just designed for that. >>>>>> >>>>>> But they say if a row doesn't exist with a ash of the key (not the >>>>> oposit, >>>>>> 2 rowkeys could have the same ash result). >>>>>> >>>>>> If you want to be sure the rowkey exists you have to search for it >> in >>>> the >>>>>> HFile ( the whole mechanism is transparent with the get() ). >>>>>> >>>>>> Their is also an KeOnlyFilter >> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html +
Asaf Mesika 2013-01-06, 20:27
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Re: Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-07, 02:14
Finally, I looked at how exists(Get) is done and build
exists(List<Get>)... (HBASE-7503) I will run some bench to compare what is faster. batch(List<Get>) or exists(List<Get>)... I build it for 0.94 too and will deploy the updated build on my cluster... 2013/1/6, Asaf Mesika <[EMAIL PROTECTED]>: > Why not write your own filter class which you can initialize with a > set of keys to search for. > The HTable on the client side will split the keys based on row keys so > it will be sent to the right regions. There your filter can utilize > SEEK_NEXT_USING_HINT Return Code to see efficiently on those set of > key values > This will ensure you do this search in one rpc call. > Your filter can also transform the KeyValue so that only the row keys > are returned > > Sent from my iPad > > On 6 בינו 2013, at 05:46, Mohamed Ibrahim <[EMAIL PROTECTED]> wrote: > >> Sorry, I didn't notice your email about packing 500 operations before. >> >> You might actually benefit from checking with a batch of Gets vs >> individual >> exists. >> >> Best, >> Mohamed >> >> >> On Sat, Jan 5, 2013 at 8:29 AM, Jean-Marc Spaggiari >> <[EMAIL PROTECTED] >>> wrote: >> >>> Hum, very interesting! >>> >>> Now, what's the best option? Array of get which will retrieve more >>> information? Or multiple HTable.exits one by one? >>> >>> The best will have been to have an array of gets passed to the >>> exist... I will see how big it is to add that... >>> >>> JM >>> >>> 2013/1/4, Mohamed Ibrahim <[EMAIL PROTECTED]>: >>>> What about HTable.exists ?? >>> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html#exists(org.apache.hadoop.hbase.client.Get) >>>> >>>> I think that should work if the Get has only the row key. >>>> >>>> Mohamed >>>> >>>> >>>> On Fri, Jan 4, 2013 at 3:17 PM, Adrien Mogenet >>>> <[EMAIL PROTECTED]>wrote: >>>> >>>>> On every Get, BloomFilter is acting as a filter (!) on top of each >>>>> HFile >>>>> and allows to check if a key is absent from the HFile. So yes, you >>>>> will >>>>> benefit from these filters. >>>>> >>>>> >>>>> On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari < >>>>> [EMAIL PROTECTED] >>>>>> wrote: >>>>> >>>>>> Is KeyOnlyFilter using the BloomFilters too? >>>>>> >>>>>> Here is, with more details, what I'm doing. >>>>>> >>>>>> Few questions. >>>>>> - Can I create one single KeyOnlyFilter and give the same filter to >>>>>> all the gets? >>>>>> - Will bloom filters benefit in such scenario? My key is small. Let's >>>>>> say average 128 bytes. >>>>>> >>>>>> The goal here is to check about 500 entries at a time to validate if >>>>>> they already exist or not. >>>>>> >>>>>> In my MR, I'm starting when I have more than 100K lines to handle, >>>>>> and >>>>>> each line car have up to 1K entries. So it can result up to 100M >>>>>> gets... Job took initially 500 minutes to complete. I have added few >>>>>> pretty good nodes and it's not taking less than 300 minutes. But I >>>>>> would like to get under 100 minutes if I can... >>>>>> >>>>>> Thanks, >>>>>> >>>>>> JM >>>>>> >>>>>> Vector<Get> gets_entry_exist = new Vector<Get>(); >>>>>> for (Entry entry : entries.getEntries()) >>>>>> { >>>>>> Get entry_exist = new Get(entry.toKey()); >>>>>> entry_exist.setFilter(new KeyOnlyFilter()); >>>>>> gets_entry_exist.add(entry_exist); >>>>>> } >>>>>> >>>>>> Result[] result_entry_exist >>>>>> table_entry.get(gets_entry_exist); >>>>>> >>>>>> int index = 0; >>>>>> for (Entry entry : entries.getEntries()) >>>>>> { >>>>>> boolean isEmpty >>>>>> result_entry_exist[index++].isEmpty(); >>>>>> if (isEmpty) >>>>>> { >>>>>> // Process here >>>>>> } >>>>>> } >>>>>> { >>>>>> >>>>>> >>>>>> 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: >>>>>>> Hello Jean-Marc, >>>>>>> >>>>>>> BloomFilters are just designed for that. +
Jean-Marc Spaggiari 2013-01-07, 02:14
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Re: Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-04, 20:28
Ok. I have activate them on 2 of my main tables and I will re-run the
job and see. 2 other questions then ;) 1) I have activated them that way: alter 'work_proposed', NAME => '@', BLOOMFILTER => 'ROW' how can I remove them? 2) Should I major_compact to make sure all the hash are stored? Thanks, JM 2013/1/4, Adrien Mogenet <[EMAIL PROTECTED]>: > On every Get, BloomFilter is acting as a filter (!) on top of each HFile > and allows to check if a key is absent from the HFile. So yes, you will > benefit from these filters. > > > On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari > <[EMAIL PROTECTED] >> wrote: > >> Is KeyOnlyFilter using the BloomFilters too? >> >> Here is, with more details, what I'm doing. >> >> Few questions. >> - Can I create one single KeyOnlyFilter and give the same filter to >> all the gets? >> - Will bloom filters benefit in such scenario? My key is small. Let's >> say average 128 bytes. >> >> The goal here is to check about 500 entries at a time to validate if >> they already exist or not. >> >> In my MR, I'm starting when I have more than 100K lines to handle, and >> each line car have up to 1K entries. So it can result up to 100M >> gets... Job took initially 500 minutes to complete. I have added few >> pretty good nodes and it's not taking less than 300 minutes. But I >> would like to get under 100 minutes if I can... >> >> Thanks, >> >> JM >> >> Vector<Get> gets_entry_exist = new Vector<Get>(); >> for (Entry entry : entries.getEntries()) >> { >> Get entry_exist = new Get(entry.toKey()); >> entry_exist.setFilter(new KeyOnlyFilter()); >> gets_entry_exist.add(entry_exist); >> } >> >> Result[] result_entry_exist = table_entry.get(gets_entry_exist); >> >> int index = 0; >> for (Entry entry : entries.getEntries()) >> { >> boolean isEmpty = result_entry_exist[index++].isEmpty(); >> if (isEmpty) >> { >> // Process here >> } >> } >> { >> >> >> 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: >> > Hello Jean-Marc, >> > >> > BloomFilters are just designed for that. >> > >> > But they say if a row doesn't exist with a ash of the key (not the >> oposit, >> > 2 rowkeys could have the same ash result). >> > >> > If you want to be sure the rowkey exists you have to search for it in >> > the >> > HFile ( the whole mechanism is transparent with the get() ). >> > >> > Their is also an KeOnlyFilter >> > >> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html >> > preventing from getting the whole columns of the existing key as return >> > (which could be heavy). >> > >> > Cheers, >> > >> > -- >> > Damien >> > >> > >> > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> >> > >> >> Hi, >> >> >> >> What's the fastest way to know if a row exist? >> >> >> >> Today I'm doing that: >> >> >> >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); >> >> Result entry_exist = table_entry.get(get_entry_exist); >> >> >> >> But should this be faster? >> >> Get get_entry_exist = new Get(key); >> >> Result entry_exist = table_entry.get(get_entry_exist); >> >> >> >> There is only one CF and one C on my table. >> >> >> >> Or is there an even faster way? >> >> >> >> Also, is there a way to make that even faster? I think BloomFilters >> >> can help, right? >> >> >> >> Thanks, >> >> >> >> JM >> >> >> > >> > > > > -- > Adrien Mogenet > 06.59.16.64.22 > http://www.mogenet.me > +
Jean-Marc Spaggiari 2013-01-04, 20:28
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Re: Fastest way to find is a row exist?Bryan Beaudreault 2013-01-04, 20:45
Why do you want to remove the bloom filter? I think you should keep the
bloom filter but also use the KeyOnlyFilter to cut down on data transferred over the wire. On Fri, Jan 4, 2013 at 3:28 PM, Jean-Marc Spaggiari <[EMAIL PROTECTED] > wrote: > Ok. I have activate them on 2 of my main tables and I will re-run the > job and see. > > 2 other questions then ;) > > 1) I have activated them that way: alter 'work_proposed', NAME => '@', > BLOOMFILTER => 'ROW' how can I remove them? > 2) Should I major_compact to make sure all the hash are stored? > > Thanks, > > JM > > 2013/1/4, Adrien Mogenet <[EMAIL PROTECTED]>: > > On every Get, BloomFilter is acting as a filter (!) on top of each HFile > > and allows to check if a key is absent from the HFile. So yes, you will > > benefit from these filters. > > > > > > On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari > > <[EMAIL PROTECTED] > >> wrote: > > > >> Is KeyOnlyFilter using the BloomFilters too? > >> > >> Here is, with more details, what I'm doing. > >> > >> Few questions. > >> - Can I create one single KeyOnlyFilter and give the same filter to > >> all the gets? > >> - Will bloom filters benefit in such scenario? My key is small. Let's > >> say average 128 bytes. > >> > >> The goal here is to check about 500 entries at a time to validate if > >> they already exist or not. > >> > >> In my MR, I'm starting when I have more than 100K lines to handle, and > >> each line car have up to 1K entries. So it can result up to 100M > >> gets... Job took initially 500 minutes to complete. I have added few > >> pretty good nodes and it's not taking less than 300 minutes. But I > >> would like to get under 100 minutes if I can... > >> > >> Thanks, > >> > >> JM > >> > >> Vector<Get> gets_entry_exist = new Vector<Get>(); > >> for (Entry entry : entries.getEntries()) > >> { > >> Get entry_exist = new Get(entry.toKey()); > >> entry_exist.setFilter(new KeyOnlyFilter()); > >> gets_entry_exist.add(entry_exist); > >> } > >> > >> Result[] result_entry_exist = table_entry.get(gets_entry_exist); > >> > >> int index = 0; > >> for (Entry entry : entries.getEntries()) > >> { > >> boolean isEmpty > result_entry_exist[index++].isEmpty(); > >> if (isEmpty) > >> { > >> // Process here > >> } > >> } > >> { > >> > >> > >> 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: > >> > Hello Jean-Marc, > >> > > >> > BloomFilters are just designed for that. > >> > > >> > But they say if a row doesn't exist with a ash of the key (not the > >> oposit, > >> > 2 rowkeys could have the same ash result). > >> > > >> > If you want to be sure the rowkey exists you have to search for it in > >> > the > >> > HFile ( the whole mechanism is transparent with the get() ). > >> > > >> > Their is also an KeOnlyFilter > >> > > >> > http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html > >> > preventing from getting the whole columns of the existing key as > return > >> > (which could be heavy). > >> > > >> > Cheers, > >> > > >> > -- > >> > Damien > >> > > >> > > >> > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> > >> > > >> >> Hi, > >> >> > >> >> What's the fastest way to know if a row exist? > >> >> > >> >> Today I'm doing that: > >> >> > >> >> Get get_entry_exist = new Get(key).addColumn(CF_DATA, C_DATA); > >> >> Result entry_exist = table_entry.get(get_entry_exist); > >> >> > >> >> But should this be faster? > >> >> Get get_entry_exist = new Get(key); > >> >> Result entry_exist = table_entry.get(get_entry_exist); > >> >> > >> >> There is only one CF and one C on my table. > >> >> > >> >> Or is there an even faster way? > >> >> > >> >> Also, is there a way to make that even faster? I think BloomFilters > >> >> can help, right? > > +
Bryan Beaudreault 2013-01-04, 20:45
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Re: Fastest way to find is a row exist?Jean-Marc Spaggiari 2013-01-04, 20:54
I want to remove it because I have set it up on the wrong column ;) I
should have used NAME => 'a' instead of ='@' ;) I have setup the kof on the code and redeployed. I have also added the bloom on the right column. I will remove the wrong one later. As soon as the compaction is done I will restart my MR and keep fingers crossed... 2013/1/4, Bryan Beaudreault <[EMAIL PROTECTED]>: > Why do you want to remove the bloom filter? I think you should keep the > bloom filter but also use the KeyOnlyFilter to cut down on data transferred > over the wire. > > > On Fri, Jan 4, 2013 at 3:28 PM, Jean-Marc Spaggiari > <[EMAIL PROTECTED] >> wrote: > >> Ok. I have activate them on 2 of my main tables and I will re-run the >> job and see. >> >> 2 other questions then ;) >> >> 1) I have activated them that way: alter 'work_proposed', NAME => '@', >> BLOOMFILTER => 'ROW' how can I remove them? >> 2) Should I major_compact to make sure all the hash are stored? >> >> Thanks, >> >> JM >> >> 2013/1/4, Adrien Mogenet <[EMAIL PROTECTED]>: >> > On every Get, BloomFilter is acting as a filter (!) on top of each >> > HFile >> > and allows to check if a key is absent from the HFile. So yes, you will >> > benefit from these filters. >> > >> > >> > On Fri, Jan 4, 2013 at 8:58 PM, Jean-Marc Spaggiari >> > <[EMAIL PROTECTED] >> >> wrote: >> > >> >> Is KeyOnlyFilter using the BloomFilters too? >> >> >> >> Here is, with more details, what I'm doing. >> >> >> >> Few questions. >> >> - Can I create one single KeyOnlyFilter and give the same filter to >> >> all the gets? >> >> - Will bloom filters benefit in such scenario? My key is small. Let's >> >> say average 128 bytes. >> >> >> >> The goal here is to check about 500 entries at a time to validate if >> >> they already exist or not. >> >> >> >> In my MR, I'm starting when I have more than 100K lines to handle, and >> >> each line car have up to 1K entries. So it can result up to 100M >> >> gets... Job took initially 500 minutes to complete. I have added few >> >> pretty good nodes and it's not taking less than 300 minutes. But I >> >> would like to get under 100 minutes if I can... >> >> >> >> Thanks, >> >> >> >> JM >> >> >> >> Vector<Get> gets_entry_exist = new Vector<Get>(); >> >> for (Entry entry : entries.getEntries()) >> >> { >> >> Get entry_exist = new Get(entry.toKey()); >> >> entry_exist.setFilter(new KeyOnlyFilter()); >> >> gets_entry_exist.add(entry_exist); >> >> } >> >> >> >> Result[] result_entry_exist >> >> table_entry.get(gets_entry_exist); >> >> >> >> int index = 0; >> >> for (Entry entry : entries.getEntries()) >> >> { >> >> boolean isEmpty >> result_entry_exist[index++].isEmpty(); >> >> if (isEmpty) >> >> { >> >> // Process here >> >> } >> >> } >> >> { >> >> >> >> >> >> 2013/1/4, Damien Hardy <[EMAIL PROTECTED]>: >> >> > Hello Jean-Marc, >> >> > >> >> > BloomFilters are just designed for that. >> >> > >> >> > But they say if a row doesn't exist with a ash of the key (not the >> >> oposit, >> >> > 2 rowkeys could have the same ash result). >> >> > >> >> > If you want to be sure the rowkey exists you have to search for it >> >> > in >> >> > the >> >> > HFile ( the whole mechanism is transparent with the get() ). >> >> > >> >> > Their is also an KeOnlyFilter >> >> > >> >> >> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/filter/KeyOnlyFilter.html >> >> > preventing from getting the whole columns of the existing key as >> return >> >> > (which could be heavy). >> >> > >> >> > Cheers, >> >> > >> >> > -- >> >> > Damien >> >> > >> >> > >> >> > 2013/1/4 Jean-Marc Spaggiari <[EMAIL PROTECTED]> >> >> > >> >> >> Hi, >> >> >> >> >> >> What's the fastest way to know if a row exist? >> >> >> >> >> >> Today I'm doing that: +
Jean-Marc Spaggiari 2013-01-04, 20:54
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