A practical approach to efficiently store 100 billions small objects in Ceph
Bonjour, In the past weeks a few mailing list threads[0][1][2] explored the problem of storing billions of small objects in Ceph. There was great feedback (I learned at lot) and it turns out the solution is a rather simple aggregation of the ideas that were suggested during these discussions. It is described in detail here: https://wiki.softwareheritage.org/wiki/A_practical_approach_to_efficiently_s... The next step will be to write and run benchmarks[3]. Although I'm convinced it is a good solution, I've been wrong before and confirmation is required :-) Many thanks to all the participants in the discussions on behalf of the Software Heritage project[4]. Cheers [0] Storing 20 billions of immutable objects in Ceph, 75% <16KB https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/JSG2TXKNXPXE... [1] Small RGW objects and RADOS 64KB minimun size https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/AEMW6O7WVJFM... [2] Using RBD to pack billions of small files https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/RHQ5ZCHJISXI... [3] https://forge.softwareheritage.org/T3054 [4] https://www.softwareheritage.org/ -- Loïc Dachary, Artisan Logiciel Libre
Bonjour Loic, I think we should all use Bonjour and Merci more often, that sounds much better than Hi, Thanks and Cheers. I am looking forward to reading your research!
-----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: 10 March 2021 15:54 To: Ceph Users <ceph-users@ceph.io> Cc: swh-devel@inria.fr Subject: [ceph-users] A practical approach to efficiently store 100 billions small objects in Ceph
Bonjour,
In the past weeks a few mailing list threads[0][1][2] explored the problem of storing billions of small objects in Ceph. There was great feedback (I learned at lot) and it turns out the solution is a rather simple aggregation of the ideas that were suggested during these discussions. It is described in detail here:
https://wiki.softwareheritage.org/wiki/A_practical_approach_to_effici ently_store_100_billions_small_objects_in_Ceph
The next step will be to write and run benchmarks[3]. Although I'm convinced it is a good solution, I've been wrong before and confirmation is required :-) Many thanks to all the participants in the discussions on behalf of the Software Heritage project[4].
Cheers
[0] Storing 20 billions of immutable objects in Ceph, 75% <16KB https://lists.ceph.io/hyperkitty/list/ceph- users@ceph.io/thread/JSG2TXKNXPXEKZOJZGYF2ZPTQHOB4LHJ/ [1] Small RGW objects and RADOS 64KB minimun size https://lists.ceph.io/hyperkitty/list/ceph- users@ceph.io/thread/AEMW6O7WVJFMUIX7QGI2KM7HKDSTNIYT/ [2] Using RBD to pack billions of small files https://lists.ceph.io/hyperkitty/list/ceph- users@ceph.io/thread/RHQ5ZCHJISXIXOJSH3TU7DLYVYHRGTAT/ [3] https://forge.softwareheritage.org/T3054 [4] https://www.softwareheritage.org/
-- Loïc Dachary, Artisan Logiciel Libre
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step [1] https://tracker.ceph.com/issues/47044 k Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks
Hi Konstantin, Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions. Cheers [0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size On 10/03/2021 17:44, Konstantin Shalygin wrote:
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step
[1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k
Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks
-- Loïc Dachary, Artisan Logiciel Libre
Does this mean that even in an object store the files which is smaller than 4MB will be packed in one 4 MB object? -----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:13 AM To: Konstantin Shalygin <k0ste@k0ste.ru> Cc: Ceph Users <ceph-users@ceph.io>; swh-devel@inria.fr Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________ Hi Konstantin, Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions. Cheers [0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size On 10/03/2021 17:44, Konstantin Shalygin wrote:
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step
[1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k
Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks
-- Loïc Dachary, Artisan Logiciel Libre ________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses.
Hi, On 11/03/2021 04:38, Szabo, Istvan (Agoda) wrote:
Does this mean that even in an object store the files which is smaller than 4MB will be packed in one 4 MB object? I'm not sure I understand the question. Would you be so kind as to rephrase it?
Cheers
-----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:13 AM To: Konstantin Shalygin <k0ste@k0ste.ru> Cc: Ceph Users <ceph-users@ceph.io>; swh-devel@inria.fr Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph
Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________
Hi Konstantin,
Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions.
Cheers
[0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size
On 10/03/2021 17:44, Konstantin Shalygin wrote:
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step
[1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k
Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks -- Loïc Dachary, Artisan Logiciel Libre
________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses.
-- Loïc Dachary, Artisan Logiciel Libre
Hi, It relates to this sentence: "The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions." Istvan Szabo Senior Infrastructure Engineer --------------------------------------------------- Agoda Services Co., Ltd. e: istvan.szabo@agoda.com --------------------------------------------------- -----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:10 PM To: Szabo, Istvan (Agoda) <Istvan.Szabo@agoda.com> Cc: Ceph Users <ceph-users@ceph.io> Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________ Hi, On 11/03/2021 04:38, Szabo, Istvan (Agoda) wrote:
Does this mean that even in an object store the files which is smaller than 4MB will be packed in one 4 MB object? I'm not sure I understand the question. Would you be so kind as to rephrase it?
Cheers
-----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:13 AM To: Konstantin Shalygin <k0ste@k0ste.ru> Cc: Ceph Users <ceph-users@ceph.io>; swh-devel@inria.fr Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph
Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________
Hi Konstantin,
Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions.
Cheers
[0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size
On 10/03/2021 17:44, Konstantin Shalygin wrote:
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step
[1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k
Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks -- Loïc Dachary, Artisan Logiciel Libre
________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses.
-- Loïc Dachary, Artisan Logiciel Libre
Thanks for clarifying, I think I understand. The idea is that 1,000 ~4KB objects are packed together in RBD which stores them in a single 4MB RADOS object. Does that answer your question? On 11/03/2021 08:22, Szabo, Istvan (Agoda) wrote:
Hi,
It relates to this sentence: "The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions."
Istvan Szabo Senior Infrastructure Engineer --------------------------------------------------- Agoda Services Co., Ltd. e: istvan.szabo@agoda.com ---------------------------------------------------
-----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:10 PM To: Szabo, Istvan (Agoda) <Istvan.Szabo@agoda.com> Cc: Ceph Users <ceph-users@ceph.io> Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph
Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________
Hi,
On 11/03/2021 04:38, Szabo, Istvan (Agoda) wrote:
Does this mean that even in an object store the files which is smaller than 4MB will be packed in one 4 MB object? I'm not sure I understand the question. Would you be so kind as to rephrase it?
Cheers
-----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:13 AM To: Konstantin Shalygin <k0ste@k0ste.ru> Cc: Ceph Users <ceph-users@ceph.io>; swh-devel@inria.fr Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph
Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________
Hi Konstantin,
Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions.
Cheers
[0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size
On 10/03/2021 17:44, Konstantin Shalygin wrote:
Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step
[1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k
Sent from my iPhone
On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote:
The next step will be to write and run benchmarks -- Loïc Dachary, Artisan Logiciel Libre
________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses. -- Loïc Dachary, Artisan Logiciel Libre
-- Loïc Dachary, Artisan Logiciel Libre
Yeah, makes sense and sounds a good idea :) I’ve never thought about this, will think in case of object store in our clusters. Istvan Szabo Senior Infrastructure Engineer --------------------------------------------------- Agoda Services Co., Ltd. e: istvan.szabo@agoda.com<mailto:istvan.szabo@agoda.com> --------------------------------------------------- On 2021. Mar 11., at 15:06, Loïc Dachary <loic@dachary.org> wrote: Thanks for clarifying, I think I understand. The idea is that 1,000 ~4KB objects are packed together in RBD which stores them in a single 4MB RADOS object. Does that answer your question? On 11/03/2021 08:22, Szabo, Istvan (Agoda) wrote: Hi, It relates to this sentence: "The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions." Istvan Szabo Senior Infrastructure Engineer --------------------------------------------------- Agoda Services Co., Ltd. e: istvan.szabo@agoda.com --------------------------------------------------- -----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:10 PM To: Szabo, Istvan (Agoda) <Istvan.Szabo@agoda.com> Cc: Ceph Users <ceph-users@ceph.io> Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________ Hi, On 11/03/2021 04:38, Szabo, Istvan (Agoda) wrote: Does this mean that even in an object store the files which is smaller than 4MB will be packed in one 4 MB object? I'm not sure I understand the question. Would you be so kind as to rephrase it? Cheers -----Original Message----- From: Loïc Dachary <loic@dachary.org> Sent: Thursday, March 11, 2021 2:13 AM To: Konstantin Shalygin <k0ste@k0ste.ru> Cc: Ceph Users <ceph-users@ceph.io>; swh-devel@inria.fr Subject: [ceph-users] Re: A practical approach to efficiently store 100 billions small objects in Ceph Email received from outside the company. If in doubt don't click links nor open attachments! ________________________________ Hi Konstantin, Thanks for the advice. Luckily objects are packed together and Ceph will only see larger objects. The median object size is ~4KB, written in RBD images using the default 4MB[0] object size. That will be ~100 millions RADOS objects instead of 100 billions. Cheers [0] https://docs.ceph.com/en/latest/man/8/rbd/#cmdoption-rbd-object-size On 10/03/2021 17:44, Konstantin Shalygin wrote: Loic, please wait (or use shaman builds) for 14.2.17 cause for clusters with billions of injects code was not optimal [1] at objects delete step [1] https://tracker.ceph.com/issues/47044 <https://tracker.ceph.com/issues/47044> k Sent from my iPhone On 10 Mar 2021, at 17:55, Loïc Dachary <loic@dachary.org> wrote: The next step will be to write and run benchmarks -- Loïc Dachary, Artisan Logiciel Libre ________________________________ This message is confidential and is for the sole use of the intended recipient(s). It may also be privileged or otherwise protected by copyright or other legal rules. If you have received it by mistake please let us know by reply email and delete it from your system. It is prohibited to copy this message or disclose its content to anyone. Any confidentiality or privilege is not waived or lost by any mistaken delivery or unauthorized disclosure of the message. All messages sent to and from Agoda may be monitored to ensure compliance with company policies, to protect the company's interests and to remove potential malware. Electronic messages may be intercepted, amended, lost or deleted, or contain viruses. -- Loïc Dachary, Artisan Logiciel Libre -- Loïc Dachary, Artisan Logiciel Libre
participants (4)
-
Konstantin Shalygin
-
Loïc Dachary
-
Marc
-
Szabo, Istvan (Agoda)