From 5cccf13ce9218f096fbdc375dbfc88a480e02b09 Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Thu, 14 Nov 2024 13:28:02 -0500 Subject: [PATCH 1/6] DOCSP-44120-mongosync-sharding-behavior --- source/reference/mongosync/mongosync-behavior.txt | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/source/reference/mongosync/mongosync-behavior.txt b/source/reference/mongosync/mongosync-behavior.txt index e83a776dc..f0cb97bc2 100644 --- a/source/reference/mongosync/mongosync-behavior.txt +++ b/source/reference/mongosync/mongosync-behavior.txt @@ -109,6 +109,20 @@ for sharded collections on the destination cluster. For each sharded collection, ``mongosync`` creates twice as many chunks as there are shards in the destination cluster. +Chunk Distribution +'''''''''''''''''' + +``mongosync`` distributes data from the source shard to all +destination shards. ``mongosync`` does not preserve cross-shard document +distribution, even with multiple ``mongosync`` binaries. It is not +posible to reproduce a particular pre-split of chunks from a source +cluster on the destination cluster. + +The only sharding configuration that ``mongosync`` preserves from the +source cluster to the destination cluster is the sharding key. Once +migration finishes, the destination cluster's balancer distributes +documents independent of the source cluster's distribution. + Primary Shards '''''''''''''' From cac070c713dd8f09ae7caef05cd7d08878c9f0b8 Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Thu, 14 Nov 2024 13:43:22 -0500 Subject: [PATCH 2/6] DOCSP-44120-mongosync-sharding-behavior --- source/faq.txt | 8 ++++++++ source/reference/mongosync/mongosync-behavior.txt | 5 ++--- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/source/faq.txt b/source/faq.txt index ad7fae829..f8567a9ba 100644 --- a/source/faq.txt +++ b/source/faq.txt @@ -171,3 +171,11 @@ Does ``mongosync`` Support TTL Indexes? {+c2c-product-name+} supports syncing :ref:`index-feature-ttl` from the source to the destination cluster. + +Can I customize chunk distributions when syncing into a sharded cluster? +------------------------------------------------------------------------ + +No, you can not configure ``mongosync`` to customize chunk +distributions. ``mongosync`` samples each collection during +initialization to determine how to distribute documents efficiently +across the destination cluster’s shards after migration. \ No newline at end of file diff --git a/source/reference/mongosync/mongosync-behavior.txt b/source/reference/mongosync/mongosync-behavior.txt index f0cb97bc2..d80d9016e 100644 --- a/source/reference/mongosync/mongosync-behavior.txt +++ b/source/reference/mongosync/mongosync-behavior.txt @@ -112,9 +112,8 @@ destination cluster. Chunk Distribution '''''''''''''''''' -``mongosync`` distributes data from the source shard to all -destination shards. ``mongosync`` does not preserve cross-shard document -distribution, even with multiple ``mongosync`` binaries. It is not +``mongosync`` does not preserve chunk distribution from the source to +the destination, even with multiple ``mongosync`` instances. It is not posible to reproduce a particular pre-split of chunks from a source cluster on the destination cluster. From bf211052f53cead402fd1f10261c98652231aa9d Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Thu, 14 Nov 2024 14:09:44 -0500 Subject: [PATCH 3/6] DOCSP-44120-mongosync-sharding-behavior --- source/faq.txt | 8 ++++---- source/reference/mongosync/mongosync-behavior.txt | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/source/faq.txt b/source/faq.txt index f8567a9ba..339da5848 100644 --- a/source/faq.txt +++ b/source/faq.txt @@ -175,7 +175,7 @@ to the destination cluster. Can I customize chunk distributions when syncing into a sharded cluster? ------------------------------------------------------------------------ -No, you can not configure ``mongosync`` to customize chunk -distributions. ``mongosync`` samples each collection during -initialization to determine how to distribute documents efficiently -across the destination cluster’s shards after migration. \ No newline at end of file +No, you can not configure ``mongosync`` to customize chunk distributions +on a destination sharded cluster. ``mongosync`` samples each collection +during initialization to determine how to distribute documents +efficiently across the destination cluster’s shards after migration. \ No newline at end of file diff --git a/source/reference/mongosync/mongosync-behavior.txt b/source/reference/mongosync/mongosync-behavior.txt index d80d9016e..6ae3eeb67 100644 --- a/source/reference/mongosync/mongosync-behavior.txt +++ b/source/reference/mongosync/mongosync-behavior.txt @@ -114,13 +114,13 @@ Chunk Distribution ``mongosync`` does not preserve chunk distribution from the source to the destination, even with multiple ``mongosync`` instances. It is not -posible to reproduce a particular pre-split of chunks from a source +possible to reproduce a particular pre-split of chunks from a source cluster on the destination cluster. The only sharding configuration that ``mongosync`` preserves from the source cluster to the destination cluster is the sharding key. Once migration finishes, the destination cluster's balancer distributes -documents independent of the source cluster's distribution. +documents independently of the source cluster's distribution. Primary Shards '''''''''''''' From dc7b5f3972f2ef760cdb4fe9822cd32e705ccd48 Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Thu, 14 Nov 2024 15:38:52 -0500 Subject: [PATCH 4/6] DOCSP-44120-FAQ --- source/faq.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/source/faq.txt b/source/faq.txt index 339da5848..ef20a57ed 100644 --- a/source/faq.txt +++ b/source/faq.txt @@ -175,7 +175,7 @@ to the destination cluster. Can I customize chunk distributions when syncing into a sharded cluster? ------------------------------------------------------------------------ -No, you can not configure ``mongosync`` to customize chunk distributions +No, you can't configure ``mongosync`` to customize chunk distributions on a destination sharded cluster. ``mongosync`` samples each collection during initialization to determine how to distribute documents efficiently across the destination cluster’s shards after migration. \ No newline at end of file From f13f306447e9991e5a2eb1ad784a06e3de0733c9 Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Mon, 18 Nov 2024 10:46:07 -0500 Subject: [PATCH 5/6] DOCSP-44120 tech edit --- source/reference/mongosync/mongosync-behavior.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/source/reference/mongosync/mongosync-behavior.txt b/source/reference/mongosync/mongosync-behavior.txt index 6ae3eeb67..9c035af26 100644 --- a/source/reference/mongosync/mongosync-behavior.txt +++ b/source/reference/mongosync/mongosync-behavior.txt @@ -118,9 +118,9 @@ possible to reproduce a particular pre-split of chunks from a source cluster on the destination cluster. The only sharding configuration that ``mongosync`` preserves from the -source cluster to the destination cluster is the sharding key. Once -migration finishes, the destination cluster's balancer distributes -documents independently of the source cluster's distribution. +source cluster to the destination cluster is the sharding key. Once the +migration finishes, you can enable the destination cluster's balancer to +distribute documents independently of the source cluster's distribution. Primary Shards '''''''''''''' From b359bf0b8d92bf1b2cdf275b5f97b4870ff664f9 Mon Sep 17 00:00:00 2001 From: Lauren Tran Date: Mon, 18 Nov 2024 10:49:55 -0500 Subject: [PATCH 6/6] DOCSP-44120 tech edit --- source/reference/mongosync/mongosync-behavior.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/source/reference/mongosync/mongosync-behavior.txt b/source/reference/mongosync/mongosync-behavior.txt index 9c035af26..8e8c92892 100644 --- a/source/reference/mongosync/mongosync-behavior.txt +++ b/source/reference/mongosync/mongosync-behavior.txt @@ -119,8 +119,8 @@ cluster on the destination cluster. The only sharding configuration that ``mongosync`` preserves from the source cluster to the destination cluster is the sharding key. Once the -migration finishes, you can enable the destination cluster's balancer to -distribute documents independently of the source cluster's distribution. +migration finishes, you can enable the destination cluster's balancer which +distributes documents independently of the source cluster's distribution. Primary Shards ''''''''''''''