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Posted to dev@iotdb.apache.org by Claude Warren <cl...@apache.org> on 2019/10/15 09:52:01 UTC
Re: Add bloom filters to TsFile
Greetings,
This is a discussion on the dev@commons.apache.org mailing list concerning
the addition of bloom filters to commons. Please take a look and comment
there.
Thx,
Claude
On Thu, Sep 12, 2019 at 3:44 PM Xiangdong Huang <sa...@gmail.com> wrote:
> +1 for bloom filter!
> +1 for implementation (but seems no license file in the repo...)
>
> By the way, it seems that there are some new variants of bloom filter,
> e.g., supporting range query.
> I am not sure whether do we need the variants, e.g., for supporting check
> whether a timeseries set "root.a.b.*.speed" exist.
>
> Best,
> -----------------------------------
> Xiangdong Huang
> School of Software, Tsinghua University
>
> 黄向东
> 清华大学 软件学院
>
>
> Claude Warren <cl...@apache.org> 于2019年9月12日周四 上午12:29写道：
>
>> In my reading of the short message it seems like it would make sense to
>> use
>> a bloom filter to determine if the "gear" is in the file. I have the
>> library that I am proposing to move to commons. It can be found at
>>
>> https://github.com/Claudenw/BloomFilter/tree/MultiFilter/src/main/java/org/xenei/bloomfilter
>>
>> Claude
>>
>> On Tue, Sep 10, 2019 at 3:45 PM Julian Feinauer <
>> j.feinauer@pragmaticminds.de> wrote:
>>
>> > Hi,
>> >
>> > I like the idea. I'm just adding Claude here as we talked yesterday
>> about
>> > a bloom filter implementation he has already done.
>> >
>> > @claude@apache.org <cl...@apache.org> what do you think? : )
>> >
>> > Julian
>> > ------------------------------
>> > *From:* Tian Jiang <jt...@163.com>
>> > *Sent:* Tuesday, September 10, 2019 5:14:33 AM
>> > *To:* dev@iotdb.apache.org <de...@iotdb.apache.org>
>> > *Subject:* Add bloom filters to TsFile
>> >
>> >
>> >
>> > Greetings,
>> >
>> >
>> > The recent readings remind me that the bloom filter is standard
>> equipment
>> > in K-VDBs. Although IoTDB is not one of them (at least not typically),
>> the
>> > bloom filter still helps a lot in various situations. For example, our
>> > recent experiments gave us an illusion that the time series in a storage
>> > group remains unchanged. However, that is not the case.
>> >
>> >
>> > Naturally, in real situations, the number of time series grows over
>> time,
>> > due to reasons like adding new gears. The old files do not contain such
>> a
>> > time series. Without the help of bloom filters, we have to check each
>> old
>> > file only to find that there is no such time series. To my knowledge,
>> this
>> > may take a lot of time.
>> >
>> >
>> > So, I suggest we add a bloom filter (or some more efficient one) to each
>> > TsFile to help skip unwanted files.
>> >
>> >
>> > | |
>> > Tian Jiang
>> > |
>> > |
>> > jt2594838@163.com
>> > |
>> > 签名由网易邮箱大师定制
>> >
>>
>
回复： Add bloom filters to TsFile
Posted by 南京大学软件学院薛恺丰 <82...@qq.com>.
Hi~
I have read the mail list carefully and Claude's code is awesome and well structured. We will have a try with your bloom filter. Thanks :D
------------------ 原始邮件 ------------------
发件人: "Claude Warren"<cl...@apache.org>;
发送时间: 2019年10月15日(星期二) 晚上8:46
收件人: "Xiangdong Huang"<sa...@gmail.com>;
抄送: "dev"<de...@iotdb.apache.org>;
主题: Re: Add bloom filters to TsFile
I would hope that the commons bloom filter would do what you need to do
without you haveing to write custom code other than some interfacing
between your objects and the hashes.
Claude
On Tue, Oct 15, 2019 at 1:43 PM Xiangdong Huang <sa...@gmail.com> wrote:
> Hi Kaifeng,
>
> > (1) Implementation of bloom filter: using BitSet implemented in java,
> the number of bits can be specified by the user
>
> Why not have a read about the discussions that Claude mentioned, you can
> find them in [1].
>
> You can evaluate whether it is suitable for TsFile, learn how Claude
> implement it, and give your opinion if you want.
>
> [1]
> https://lists.apache.org/list.html?dev@commons.apache.org:lte=1M:bloom%20filter
>
> Best,
> -----------------------------------
> Xiangdong Huang
> School of Software, Tsinghua University
>
> 黄向东
> 清华大学 软件学院
>
>
> 南京大学软件学院薛恺丰 <82...@qq.com> 于2019年10月15日周二 下午7:10写道：
>
>> Hi~
>> Here are my ideas:
>>
>>
>> Problem: When the server runs for a period of time, there will be many
>> fragmented tsfiles. The storage groups in these tsfiles are different. When
>> a query comes, we must load the metadata of each tsfile to determine
>> whether the specified time series exists in the tsfile.
>>
>>
>> Solution: create a bloom filter for the time series contained in each
>> tsfile. If the specified time series does not exist, we do not need to read
>> metadata.
>>
>>
>> Design:
>> (1) Implementation of bloom filter: using BitSet implemented in java, the
>> number of bits can be specified by the user
>> (2) storage location and size: it is stored in the last part of metadata.
>> The specific data is as follows: BitSet size (int), BitSet
>>
>>
>> Interface:
>> Add the getBloomFilter interface to TsfileMetadata to get the bloom
>> filter, and use its "contains" method to determine whether a path exists in
>> the tsfile
>>
>>
>>
>> If you have some ideas, please feel free to discuss with me. :D
>>
>>
>>
>>
>> ------------------ 原始邮件 ------------------
>> 发件人: "Claude Warren"<cl...@apache.org>;
>> 发送时间: 2019年10月15日(星期二) 下午5:52
>> 收件人: "Xiangdong Huang"<sa...@gmail.com>;"Julian Feinauer"<
>> j.feinauer@pragmaticminds.de>;
>> 抄送: "dev"<de...@iotdb.apache.org>;
>> 主题: Re: Add bloom filters to TsFile
>>
>>
>>
>> Greetings,
>>
>> This is a discussion on the dev@commons.apache.org mailing list
>> concerning
>> the addition of bloom filters to commons. Please take a look and comment
>> there.
>>
>> Thx,
>> Claude
>>
>> On Thu, Sep 12, 2019 at 3:44 PM Xiangdong Huang <sa...@gmail.com>
>> wrote:
>>
>> > +1 for bloom filter!
>> > +1 for implementation (but seems no license file in the repo...)
>> >
>> > By the way, it seems that there are some new variants of bloom filter,
>> > e.g., supporting range query.
>> > I am not sure whether do we need the variants, e.g., for supporting
>> check
>> > whether a timeseries set "root.a.b.*.speed" exist.
>> >
>> > Best,
>> > -----------------------------------
>> > Xiangdong Huang
>> > School of Software, Tsinghua University
>> >
>> > 黄向东
>> > 清华大学 软件学院
>> >
>> >
>> > Claude Warren <cl...@apache.org> 于2019年9月12日周四 上午12:29写道：
>> >
>> >> In my reading of the short message it seems like it would make sense to
>> >> use
>> >> a bloom filter to determine if the "gear" is in the file. I have the
>> >> library that I am proposing to move to commons. It can be found at
>> >>
>> >>
>> https://github.com/Claudenw/BloomFilter/tree/MultiFilter/src/main/java/org/xenei/bloomfilter
>> >>
>> >> Claude
>> >>
>> >> On Tue, Sep 10, 2019 at 3:45 PM Julian Feinauer <
>> >> j.feinauer@pragmaticminds.de> wrote:
>> >>
>> >> > Hi,
>> >> >
>> >> > I like the idea. I'm just adding Claude here as we talked yesterday
>> >> about
>> >> > a bloom filter implementation he has already done.
>> >> >
>> >> > @claude@apache.org <cl...@apache.org> what do you think? : )
>> >> >
>> >> > Julian
>> >> > ------------------------------
>> >> > *From:* Tian Jiang <jt...@163.com>
>> >> > *Sent:* Tuesday, September 10, 2019 5:14:33 AM
>> >> > *To:* dev@iotdb.apache.org <de...@iotdb.apache.org>
>> >> > *Subject:* Add bloom filters to TsFile
>> >> >
>> >> >
>> >> >
>> >> > Greetings,
>> >> >
>> >> >
>> >> > The recent readings remind me that the bloom filter is standard
>> >> equipment
>> >> > in K-VDBs. Although IoTDB is not one of them (at least not
>> typically),
>> >> the
>> >> > bloom filter still helps a lot in various situations. For example,
>> our
>> >> > recent experiments gave us an illusion that the time series in a
>> storage
>> >> > group remains unchanged. However, that is not the case.
>> >> >
>> >> >
>> >> > Naturally, in real situations, the number of time series grows over
>> >> time,
>> >> > due to reasons like adding new gears. The old files do not contain
>> such
>> >> a
>> >> > time series. Without the help of bloom filters, we have to check each
>> >> old
>> >> > file only to find that there is no such time series. To my knowledge,
>> >> this
>> >> > may take a lot of time.
>> >> >
>> >> >
>> >> > So, I suggest we add a bloom filter (or some more efficient one) to
>> each
>> >> > TsFile to help skip unwanted files.
>> >> >
>> >> >
>> >> > | |
>> >> > Tian Jiang
>> >> > |
>> >> > |
>> >> > jt2594838@163.com
>> >> > |
>> >> > 签名由网易邮箱大师定制
>> >> >
>> >>
>> >
>
>
Re: Add bloom filters to TsFile
Posted by Claude Warren <cl...@apache.org>.
I would hope that the commons bloom filter would do what you need to do
without you haveing to write custom code other than some interfacing
between your objects and the hashes.
Claude
On Tue, Oct 15, 2019 at 1:43 PM Xiangdong Huang <sa...@gmail.com> wrote:
> Hi Kaifeng,
>
> > (1) Implementation of bloom filter: using BitSet implemented in java,
> the number of bits can be specified by the user
>
> Why not have a read about the discussions that Claude mentioned, you can
> find them in [1].
>
> You can evaluate whether it is suitable for TsFile, learn how Claude
> implement it, and give your opinion if you want.
>
> [1]
> https://lists.apache.org/list.html?dev@commons.apache.org:lte=1M:bloom%20filter
>
> Best,
> -----------------------------------
> Xiangdong Huang
> School of Software, Tsinghua University
>
> 黄向东
> 清华大学 软件学院
>
>
> 南京大学软件学院薛恺丰 <82...@qq.com> 于2019年10月15日周二 下午7:10写道：
>
>> Hi~
>> Here are my ideas:
>>
>>
>> Problem: When the server runs for a period of time, there will be many
>> fragmented tsfiles. The storage groups in these tsfiles are different. When
>> a query comes, we must load the metadata of each tsfile to determine
>> whether the specified time series exists in the tsfile.
>>
>>
>> Solution: create a bloom filter for the time series contained in each
>> tsfile. If the specified time series does not exist, we do not need to read
>> metadata.
>>
>>
>> Design:
>> (1) Implementation of bloom filter: using BitSet implemented in java, the
>> number of bits can be specified by the user
>> (2) storage location and size: it is stored in the last part of metadata.
>> The specific data is as follows: BitSet size (int), BitSet
>>
>>
>> Interface:
>> Add the getBloomFilter interface to TsfileMetadata to get the bloom
>> filter, and use its "contains" method to determine whether a path exists in
>> the tsfile
>>
>>
>>
>> If you have some ideas, please feel free to discuss with me. :D
>>
>>
>>
>>
>> ------------------ 原始邮件 ------------------
>> 发件人: "Claude Warren"<cl...@apache.org>;
>> 发送时间: 2019年10月15日(星期二) 下午5:52
>> 收件人: "Xiangdong Huang"<sa...@gmail.com>;"Julian Feinauer"<
>> j.feinauer@pragmaticminds.de>;
>> 抄送: "dev"<de...@iotdb.apache.org>;
>> 主题: Re: Add bloom filters to TsFile
>>
>>
>>
>> Greetings,
>>
>> This is a discussion on the dev@commons.apache.org mailing list
>> concerning
>> the addition of bloom filters to commons. Please take a look and comment
>> there.
>>
>> Thx,
>> Claude
>>
>> On Thu, Sep 12, 2019 at 3:44 PM Xiangdong Huang <sa...@gmail.com>
>> wrote:
>>
>> > +1 for bloom filter!
>> > +1 for implementation (but seems no license file in the repo...)
>> >
>> > By the way, it seems that there are some new variants of bloom filter,
>> > e.g., supporting range query.
>> > I am not sure whether do we need the variants, e.g., for supporting
>> check
>> > whether a timeseries set "root.a.b.*.speed" exist.
>> >
>> > Best,
>> > -----------------------------------
>> > Xiangdong Huang
>> > School of Software, Tsinghua University
>> >
>> > 黄向东
>> > 清华大学 软件学院
>> >
>> >
>> > Claude Warren <cl...@apache.org> 于2019年9月12日周四 上午12:29写道：
>> >
>> >> In my reading of the short message it seems like it would make sense to
>> >> use
>> >> a bloom filter to determine if the "gear" is in the file. I have the
>> >> library that I am proposing to move to commons. It can be found at
>> >>
>> >>
>> https://github.com/Claudenw/BloomFilter/tree/MultiFilter/src/main/java/org/xenei/bloomfilter
>> >>
>> >> Claude
>> >>
>> >> On Tue, Sep 10, 2019 at 3:45 PM Julian Feinauer <
>> >> j.feinauer@pragmaticminds.de> wrote:
>> >>
>> >> > Hi,
>> >> >
>> >> > I like the idea. I'm just adding Claude here as we talked yesterday
>> >> about
>> >> > a bloom filter implementation he has already done.
>> >> >
>> >> > @claude@apache.org <cl...@apache.org> what do you think? : )
>> >> >
>> >> > Julian
>> >> > ------------------------------
>> >> > *From:* Tian Jiang <jt...@163.com>
>> >> > *Sent:* Tuesday, September 10, 2019 5:14:33 AM
>> >> > *To:* dev@iotdb.apache.org <de...@iotdb.apache.org>
>> >> > *Subject:* Add bloom filters to TsFile
>> >> >
>> >> >
>> >> >
>> >> > Greetings,
>> >> >
>> >> >
>> >> > The recent readings remind me that the bloom filter is standard
>> >> equipment
>> >> > in K-VDBs. Although IoTDB is not one of them (at least not
>> typically),
>> >> the
>> >> > bloom filter still helps a lot in various situations. For example,
>> our
>> >> > recent experiments gave us an illusion that the time series in a
>> storage
>> >> > group remains unchanged. However, that is not the case.
>> >> >
>> >> >
>> >> > Naturally, in real situations, the number of time series grows over
>> >> time,
>> >> > due to reasons like adding new gears. The old files do not contain
>> such
>> >> a
>> >> > time series. Without the help of bloom filters, we have to check each
>> >> old
>> >> > file only to find that there is no such time series. To my knowledge,
>> >> this
>> >> > may take a lot of time.
>> >> >
>> >> >
>> >> > So, I suggest we add a bloom filter (or some more efficient one) to
>> each
>> >> > TsFile to help skip unwanted files.
>> >> >
>> >> >
>> >> > | |
>> >> > Tian Jiang
>> >> > |
>> >> > |
>> >> > jt2594838@163.com
>> >> > |
>> >> > 签名由网易邮箱大师定制
>> >> >
>> >>
>> >
>
>
Re: Add bloom filters to TsFile
Posted by Xiangdong Huang <sa...@gmail.com>.
Hi Kaifeng,
> (1) Implementation of bloom filter: using BitSet implemented in java, the
number of bits can be specified by the user
Why not have a read about the discussions that Claude mentioned, you can
find them in [1].
You can evaluate whether it is suitable for TsFile, learn how Claude
implement it, and give your opinion if you want.
[1]
https://lists.apache.org/list.html?dev@commons.apache.org:lte=1M:bloom%20filter
Best,
-----------------------------------
Xiangdong Huang
School of Software, Tsinghua University
黄向东
清华大学 软件学院
南京大学软件学院薛恺丰 <82...@qq.com> 于2019年10月15日周二 下午7:10写道：
> Hi~
> Here are my ideas:
>
>
> Problem: When the server runs for a period of time, there will be many
> fragmented tsfiles. The storage groups in these tsfiles are different. When
> a query comes, we must load the metadata of each tsfile to determine
> whether the specified time series exists in the tsfile.
>
>
> Solution: create a bloom filter for the time series contained in each
> tsfile. If the specified time series does not exist, we do not need to read
> metadata.
>
>
> Design:
> (1) Implementation of bloom filter: using BitSet implemented in java, the
> number of bits can be specified by the user
> (2) storage location and size: it is stored in the last part of metadata.
> The specific data is as follows: BitSet size (int), BitSet
>
>
> Interface:
> Add the getBloomFilter interface to TsfileMetadata to get the bloom
> filter, and use its "contains" method to determine whether a path exists in
> the tsfile
>
>
>
> If you have some ideas, please feel free to discuss with me. :D
>
>
>
>
> ------------------ 原始邮件 ------------------
> 发件人: "Claude Warren"<cl...@apache.org>;
> 发送时间: 2019年10月15日(星期二) 下午5:52
> 收件人: "Xiangdong Huang"<sa...@gmail.com>;"Julian Feinauer"<
> j.feinauer@pragmaticminds.de>;
> 抄送: "dev"<de...@iotdb.apache.org>;
> 主题: Re: Add bloom filters to TsFile
>
>
>
> Greetings,
>
> This is a discussion on the dev@commons.apache.org mailing list concerning
> the addition of bloom filters to commons. Please take a look and comment
> there.
>
> Thx,
> Claude
>
> On Thu, Sep 12, 2019 at 3:44 PM Xiangdong Huang <sa...@gmail.com>
> wrote:
>
> > +1 for bloom filter!
> > +1 for implementation (but seems no license file in the repo...)
> >
> > By the way, it seems that there are some new variants of bloom filter,
> > e.g., supporting range query.
> > I am not sure whether do we need the variants, e.g., for supporting check
> > whether a timeseries set "root.a.b.*.speed" exist.
> >
> > Best,
> > -----------------------------------
> > Xiangdong Huang
> > School of Software, Tsinghua University
> >
> > 黄向东
> > 清华大学 软件学院
> >
> >
> > Claude Warren <cl...@apache.org> 于2019年9月12日周四 上午12:29写道：
> >
> >> In my reading of the short message it seems like it would make sense to
> >> use
> >> a bloom filter to determine if the "gear" is in the file. I have the
> >> library that I am proposing to move to commons. It can be found at
> >>
> >>
> https://github.com/Claudenw/BloomFilter/tree/MultiFilter/src/main/java/org/xenei/bloomfilter
> >>
> >> Claude
> >>
> >> On Tue, Sep 10, 2019 at 3:45 PM Julian Feinauer <
> >> j.feinauer@pragmaticminds.de> wrote:
> >>
> >> > Hi,
> >> >
> >> > I like the idea. I'm just adding Claude here as we talked yesterday
> >> about
> >> > a bloom filter implementation he has already done.
> >> >
> >> > @claude@apache.org <cl...@apache.org> what do you think? : )
> >> >
> >> > Julian
> >> > ------------------------------
> >> > *From:* Tian Jiang <jt...@163.com>
> >> > *Sent:* Tuesday, September 10, 2019 5:14:33 AM
> >> > *To:* dev@iotdb.apache.org <de...@iotdb.apache.org>
> >> > *Subject:* Add bloom filters to TsFile
> >> >
> >> >
> >> >
> >> > Greetings,
> >> >
> >> >
> >> > The recent readings remind me that the bloom filter is standard
> >> equipment
> >> > in K-VDBs. Although IoTDB is not one of them (at least not typically),
> >> the
> >> > bloom filter still helps a lot in various situations. For example, our
> >> > recent experiments gave us an illusion that the time series in a
> storage
> >> > group remains unchanged. However, that is not the case.
> >> >
> >> >
> >> > Naturally, in real situations, the number of time series grows over
> >> time,
> >> > due to reasons like adding new gears. The old files do not contain
> such
> >> a
> >> > time series. Without the help of bloom filters, we have to check each
> >> old
> >> > file only to find that there is no such time series. To my knowledge,
> >> this
> >> > may take a lot of time.
> >> >
> >> >
> >> > So, I suggest we add a bloom filter (or some more efficient one) to
> each
> >> > TsFile to help skip unwanted files.
> >> >
> >> >
> >> > | |
> >> > Tian Jiang
> >> > |
> >> > |
> >> > jt2594838@163.com
> >> > |
> >> > 签名由网易邮箱大师定制
> >> >
> >>
> >
回复： Add bloom filters to TsFile
Posted by 南京大学软件学院薛恺丰 <82...@qq.com>.
Hi~
Here are my ideas:
Problem: When the server runs for a period of time, there will be many fragmented tsfiles. The storage groups in these tsfiles are different. When a query comes, we must load the metadata of each tsfile to determine whether the specified time series exists in the tsfile.
Solution: create a bloom filter for the time series contained in each tsfile. If the specified time series does not exist, we do not need to read metadata.
Design:
(1) Implementation of bloom filter: using BitSet implemented in java, the number of bits can be specified by the user
(2) storage location and size: it is stored in the last part of metadata. The specific data is as follows: BitSet size (int), BitSet
Interface:
Add the getBloomFilter interface to TsfileMetadata to get the bloom filter, and use its "contains" method to determine whether a path exists in the tsfile
If you have some ideas, please feel free to discuss with me. :D
------------------ 原始邮件 ------------------
发件人: "Claude Warren"<cl...@apache.org>;
发送时间: 2019年10月15日(星期二) 下午5:52
收件人: "Xiangdong Huang"<sa...@gmail.com>;"Julian Feinauer"<j....@pragmaticminds.de>;
抄送: "dev"<de...@iotdb.apache.org>;
主题: Re: Add bloom filters to TsFile
Greetings,
This is a discussion on the dev@commons.apache.org mailing list concerning
the addition of bloom filters to commons. Please take a look and comment
there.
Thx,
Claude
On Thu, Sep 12, 2019 at 3:44 PM Xiangdong Huang <sa...@gmail.com> wrote:
> +1 for bloom filter!
> +1 for implementation (but seems no license file in the repo...)
>
> By the way, it seems that there are some new variants of bloom filter,
> e.g., supporting range query.
> I am not sure whether do we need the variants, e.g., for supporting check
> whether a timeseries set "root.a.b.*.speed" exist.
>
> Best,
> -----------------------------------
> Xiangdong Huang
> School of Software, Tsinghua University
>
> 黄向东
> 清华大学 软件学院
>
>
> Claude Warren <cl...@apache.org> 于2019年9月12日周四 上午12:29写道：
>
>> In my reading of the short message it seems like it would make sense to
>> use
>> a bloom filter to determine if the "gear" is in the file. I have the
>> library that I am proposing to move to commons. It can be found at
>>
>> https://github.com/Claudenw/BloomFilter/tree/MultiFilter/src/main/java/org/xenei/bloomfilter
>>
>> Claude
>>
>> On Tue, Sep 10, 2019 at 3:45 PM Julian Feinauer <
>> j.feinauer@pragmaticminds.de> wrote:
>>
>> > Hi,
>> >
>> > I like the idea. I'm just adding Claude here as we talked yesterday
>> about
>> > a bloom filter implementation he has already done.
>> >
>> > @claude@apache.org <cl...@apache.org> what do you think? : )
>> >
>> > Julian
>> > ------------------------------
>> > *From:* Tian Jiang <jt...@163.com>
>> > *Sent:* Tuesday, September 10, 2019 5:14:33 AM
>> > *To:* dev@iotdb.apache.org <de...@iotdb.apache.org>
>> > *Subject:* Add bloom filters to TsFile
>> >
>> >
>> >
>> > Greetings,
>> >
>> >
>> > The recent readings remind me that the bloom filter is standard
>> equipment
>> > in K-VDBs. Although IoTDB is not one of them (at least not typically),
>> the
>> > bloom filter still helps a lot in various situations. For example, our
>> > recent experiments gave us an illusion that the time series in a storage
>> > group remains unchanged. However, that is not the case.
>> >
>> >
>> > Naturally, in real situations, the number of time series grows over
>> time,
>> > due to reasons like adding new gears. The old files do not contain such
>> a
>> > time series. Without the help of bloom filters, we have to check each
>> old
>> > file only to find that there is no such time series. To my knowledge,
>> this
>> > may take a lot of time.
>> >
>> >
>> > So, I suggest we add a bloom filter (or some more efficient one) to each
>> > TsFile to help skip unwanted files.
>> >
>> >
>> > | |
>> > Tian Jiang
>> > |
>> > |
>> > jt2594838@163.com
>> > |
>> > 签名由网易邮箱大师定制
>> >
>>
>