[chore] Use bulk updates + fewer loops in status rethreading migration (#4459)

This pull request tries to optimize our status rethreading migration by using bulk updates + avoiding unnecessary writes, and doing the migration in one top-level loop and one stragglers loop, without the extra loop to copy thread_id over.

On my machine it runs at about 2400 rows per second on Postgres, now, and about 9000 rows per second on SQLite.

Tried *many* different ways of doing this, with and without temporary indexes, with different batch and transaction sizes, etc., and this seems to be just about the most performant way of getting stuff done.

With the changes, a few minutes have been shaved off migration time testing on my development machine. *Hopefully* this will translate to more time shaved off when running on a vps with slower read/write speed and less processor power.

SQLite before:

```
real	20m58,446s
user	16m26,635s
sys	5m53,648s
```

SQLite after:

```
real	14m25,435s
user	12m47,449s
sys	2m27,898s
```

Postgres before:

```
real	28m25,307s
user	3m40,005s
sys	4m45,018s
```

Postgres after:

```
real	22m31,999s
user	3m46,674s
sys	4m39,592s
```

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4459
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Co-committed-by: tobi <tobi.smethurst@protonmail.com>

1 files changed, 50 insertions, 50 deletions

diff --git a/internal/gtsmodel/status.go b/internal/gtsmodel/status.go
index 31e8fe881..0f0fb8404 100644
--- a/internal/gtsmodel/status.go
+++ b/internal/gtsmodel/status.go
@@ -27,56 +27,56 @@ import (
 
 // Status represents a user-created 'post' or 'status' in the database, either remote or local
 type Status struct {
-	ID                       string             `bun:"type:CHAR(26),pk,nullzero,notnull,unique"`                          // id of this item in the database
-	CreatedAt                time.Time          `bun:"type:timestamptz,nullzero,notnull,default:current_timestamp"`       // when was item created
-	EditedAt                 time.Time          `bun:"type:timestamptz,nullzero"`                                         // when this status was last edited (if set)
-	FetchedAt                time.Time          `bun:"type:timestamptz,nullzero"`                                         // when was item (remote) last fetched.
-	PinnedAt                 time.Time          `bun:"type:timestamptz,nullzero"`                                         // Status was pinned by owning account at this time.
-	URI                      string             `bun:",unique,nullzero,notnull"`                                          // activitypub URI of this status
-	URL                      string             `bun:",nullzero"`                                                         // web url for viewing this status
-	Content                  string             `bun:""`                                                                  // Content HTML for this status.
-	AttachmentIDs            []string           `bun:"attachments,array"`                                                 // Database IDs of any media attachments associated with this status
-	Attachments              []*MediaAttachment `bun:"attached_media,rel:has-many"`                                       // Attachments corresponding to attachmentIDs
-	TagIDs                   []string           `bun:"tags,array"`                                                        // Database IDs of any tags used in this status
-	Tags                     []*Tag             `bun:"attached_tags,m2m:status_to_tags"`                                  // Tags corresponding to tagIDs. https://bun.uptrace.dev/guide/relations.html#many-to-many-relation
-	MentionIDs               []string           `bun:"mentions,array"`                                                    // Database IDs of any mentions in this status
-	Mentions                 []*Mention         `bun:"attached_mentions,rel:has-many"`                                    // Mentions corresponding to mentionIDs
-	EmojiIDs                 []string           `bun:"emojis,array"`                                                      // Database IDs of any emojis used in this status
-	Emojis                   []*Emoji           `bun:"attached_emojis,m2m:status_to_emojis"`                              // Emojis corresponding to emojiIDs. https://bun.uptrace.dev/guide/relations.html#many-to-many-relation
-	Local                    *bool              `bun:",nullzero,notnull,default:false"`                                   // is this status from a local account?
-	AccountID                string             `bun:"type:CHAR(26),nullzero,notnull"`                                    // which account posted this status?
-	Account                  *Account           `bun:"rel:belongs-to"`                                                    // account corresponding to accountID
-	AccountURI               string             `bun:",nullzero,notnull"`                                                 // activitypub uri of the owner of this status
-	InReplyToID              string             `bun:"type:CHAR(26),nullzero"`                                            // id of the status this status replies to
-	InReplyToURI             string             `bun:",nullzero"`                                                         // activitypub uri of the status this status is a reply to
-	InReplyToAccountID       string             `bun:"type:CHAR(26),nullzero"`                                            // id of the account that this status replies to
-	InReplyTo                *Status            `bun:"-"`                                                                 // status corresponding to inReplyToID
-	InReplyToAccount         *Account           `bun:"rel:belongs-to"`                                                    // account corresponding to inReplyToAccountID
-	BoostOfID                string             `bun:"type:CHAR(26),nullzero"`                                            // id of the status this status is a boost of
-	BoostOfURI               string             `bun:"-"`                                                                 // URI of the status this status is a boost of; field not inserted in the db, just for dereferencing purposes.
-	BoostOfAccountID         string             `bun:"type:CHAR(26),nullzero"`                                            // id of the account that owns the boosted status
-	BoostOf                  *Status            `bun:"-"`                                                                 // status that corresponds to boostOfID
-	BoostOfAccount           *Account           `bun:"rel:belongs-to"`                                                    // account that corresponds to boostOfAccountID
-	ThreadID                 string             `bun:"type:CHAR(26),nullzero,notnull,default:00000000000000000000000000"` // id of the thread to which this status belongs
-	EditIDs                  []string           `bun:"edits,array"`                                                       // IDs of status edits for this status, ordered from smallest (oldest) -> largest (newest) ID.
-	Edits                    []*StatusEdit      `bun:"-"`                                                                 // Edits of this status, ordered from oldest -> newest edit.
-	PollID                   string             `bun:"type:CHAR(26),nullzero"`                                            //
-	Poll                     *Poll              `bun:"-"`                                                                 //
-	ContentWarning           string             `bun:",nullzero"`                                                         // Content warning HTML for this status.
-	ContentWarningText       string             `bun:""`                                                                  // Original text of the content warning without formatting
-	Visibility               Visibility         `bun:",nullzero,notnull"`                                                 // visibility entry for this status
-	Sensitive                *bool              `bun:",nullzero,notnull,default:false"`                                   // mark the status as sensitive?
-	Language                 string             `bun:",nullzero"`                                                         // what language is this status written in?
-	CreatedWithApplicationID string             `bun:"type:CHAR(26),nullzero"`                                            // Which application was used to create this status?
-	CreatedWithApplication   *Application       `bun:"rel:belongs-to"`                                                    // application corresponding to createdWithApplicationID
-	ActivityStreamsType      string             `bun:",nullzero,notnull"`                                                 // What is the activitystreams type of this status? See: https://www.w3.org/TR/activitystreams-vocabulary/#object-types. Will probably almost always be Note but who knows!.
-	Text                     string             `bun:""`                                                                  // Original text of the status without formatting
-	ContentType              StatusContentType  `bun:",nullzero"`                                                         // Content type used to process the original text of the status
-	Federated                *bool              `bun:",notnull"`                                                          // This status will be federated beyond the local timeline(s)
-	InteractionPolicy        *InteractionPolicy `bun:""`                                                                  // InteractionPolicy for this status. If null then the default InteractionPolicy should be assumed for this status's Visibility. Always null for boost wrappers.
-	PendingApproval          *bool              `bun:",nullzero,notnull,default:false"`                                   // If true then status is a reply or boost wrapper that must be Approved by the reply-ee or boost-ee before being fully distributed.
-	PreApproved              bool               `bun:"-"`                                                                 // If true, then status is a reply to or boost wrapper of a status on our instance, has permission to do the interaction, and an Accept should be sent out for it immediately. Field not stored in the DB.
-	ApprovedByURI            string             `bun:",nullzero"`                                                         // URI of *either* an Accept Activity, or a ReplyAuthorization or AnnounceAuthorization, which approves the Announce, Create or interaction request Activity that this status was/will be attached to.
+	ID                       string             `bun:"type:CHAR(26),pk,nullzero,notnull,unique"`                            // id of this item in the database
+	CreatedAt                time.Time          `bun:"type:timestamptz,nullzero,notnull,default:current_timestamp"`         // when was item created
+	EditedAt                 time.Time          `bun:"type:timestamptz,nullzero"`                                           // when this status was last edited (if set)
+	FetchedAt                time.Time          `bun:"type:timestamptz,nullzero"`                                           // when was item (remote) last fetched.
+	PinnedAt                 time.Time          `bun:"type:timestamptz,nullzero"`                                           // Status was pinned by owning account at this time.
+	URI                      string             `bun:",unique,nullzero,notnull"`                                            // activitypub URI of this status
+	URL                      string             `bun:",nullzero"`                                                           // web url for viewing this status
+	Content                  string             `bun:""`                                                                    // Content HTML for this status.
+	AttachmentIDs            []string           `bun:"attachments,array"`                                                   // Database IDs of any media attachments associated with this status
+	Attachments              []*MediaAttachment `bun:"attached_media,rel:has-many"`                                         // Attachments corresponding to attachmentIDs
+	TagIDs                   []string           `bun:"tags,array"`                                                          // Database IDs of any tags used in this status
+	Tags                     []*Tag             `bun:"attached_tags,m2m:status_to_tags"`                                    // Tags corresponding to tagIDs. https://bun.uptrace.dev/guide/relations.html#many-to-many-relation
+	MentionIDs               []string           `bun:"mentions,array"`                                                      // Database IDs of any mentions in this status
+	Mentions                 []*Mention         `bun:"attached_mentions,rel:has-many"`                                      // Mentions corresponding to mentionIDs
+	EmojiIDs                 []string           `bun:"emojis,array"`                                                        // Database IDs of any emojis used in this status
+	Emojis                   []*Emoji           `bun:"attached_emojis,m2m:status_to_emojis"`                                // Emojis corresponding to emojiIDs. https://bun.uptrace.dev/guide/relations.html#many-to-many-relation
+	Local                    *bool              `bun:",nullzero,notnull,default:false"`                                     // is this status from a local account?
+	AccountID                string             `bun:"type:CHAR(26),nullzero,notnull"`                                      // which account posted this status?
+	Account                  *Account           `bun:"rel:belongs-to"`                                                      // account corresponding to accountID
+	AccountURI               string             `bun:",nullzero,notnull"`                                                   // activitypub uri of the owner of this status
+	InReplyToID              string             `bun:"type:CHAR(26),nullzero"`                                              // id of the status this status replies to
+	InReplyToURI             string             `bun:",nullzero"`                                                           // activitypub uri of the status this status is a reply to
+	InReplyToAccountID       string             `bun:"type:CHAR(26),nullzero"`                                              // id of the account that this status replies to
+	InReplyTo                *Status            `bun:"-"`                                                                   // status corresponding to inReplyToID
+	InReplyToAccount         *Account           `bun:"rel:belongs-to"`                                                      // account corresponding to inReplyToAccountID
+	BoostOfID                string             `bun:"type:CHAR(26),nullzero"`                                              // id of the status this status is a boost of
+	BoostOfURI               string             `bun:"-"`                                                                   // URI of the status this status is a boost of; field not inserted in the db, just for dereferencing purposes.
+	BoostOfAccountID         string             `bun:"type:CHAR(26),nullzero"`                                              // id of the account that owns the boosted status
+	BoostOf                  *Status            `bun:"-"`                                                                   // status that corresponds to boostOfID
+	BoostOfAccount           *Account           `bun:"rel:belongs-to"`                                                      // account that corresponds to boostOfAccountID
+	ThreadID                 string             `bun:"type:CHAR(26),nullzero,notnull,default:'00000000000000000000000000'"` // id of the thread to which this status belongs
+	EditIDs                  []string           `bun:"edits,array"`                                                         // IDs of status edits for this status, ordered from smallest (oldest) -> largest (newest) ID.
+	Edits                    []*StatusEdit      `bun:"-"`                                                                   // Edits of this status, ordered from oldest -> newest edit.
+	PollID                   string             `bun:"type:CHAR(26),nullzero"`                                              //
+	Poll                     *Poll              `bun:"-"`                                                                   //
+	ContentWarning           string             `bun:",nullzero"`                                                           // Content warning HTML for this status.
+	ContentWarningText       string             `bun:""`                                                                    // Original text of the content warning without formatting
+	Visibility               Visibility         `bun:",nullzero,notnull"`                                                   // visibility entry for this status
+	Sensitive                *bool              `bun:",nullzero,notnull,default:false"`                                     // mark the status as sensitive?
+	Language                 string             `bun:",nullzero"`                                                           // what language is this status written in?
+	CreatedWithApplicationID string             `bun:"type:CHAR(26),nullzero"`                                              // Which application was used to create this status?
+	CreatedWithApplication   *Application       `bun:"rel:belongs-to"`                                                      // application corresponding to createdWithApplicationID
+	ActivityStreamsType      string             `bun:",nullzero,notnull"`                                                   // What is the activitystreams type of this status? See: https://www.w3.org/TR/activitystreams-vocabulary/#object-types. Will probably almost always be Note but who knows!.
+	Text                     string             `bun:""`                                                                    // Original text of the status without formatting
+	ContentType              StatusContentType  `bun:",nullzero"`                                                           // Content type used to process the original text of the status
+	Federated                *bool              `bun:",notnull"`                                                            // This status will be federated beyond the local timeline(s)
+	InteractionPolicy        *InteractionPolicy `bun:""`                                                                    // InteractionPolicy for this status. If null then the default InteractionPolicy should be assumed for this status's Visibility. Always null for boost wrappers.
+	PendingApproval          *bool              `bun:",nullzero,notnull,default:false"`                                     // If true then status is a reply or boost wrapper that must be Approved by the reply-ee or boost-ee before being fully distributed.
+	PreApproved              bool               `bun:"-"`                                                                   // If true, then status is a reply to or boost wrapper of a status on our instance, has permission to do the interaction, and an Accept should be sent out for it immediately. Field not stored in the DB.
+	ApprovedByURI            string             `bun:",nullzero"`                                                           // URI of *either* an Accept Activity, or a ReplyAuthorization or AnnounceAuthorization, which approves the Announce, Create or interaction request Activity that this status was/will be attached to.
 }
 
 // GetID implements timeline.Timelineable{}.