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https://issues.apache.org/jira/browse/IGNITE-23120?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17986509#comment-17986509
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Philipp Shergalis edited comment on IGNITE-23120 at 6/27/25 9:56 AM:
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[~timonin.maksim] Client nodes calculate inline size (for INDEXES system view):
{code:java}
ClientIndexDefinition def = new ClientIndexDefinition(idxFullName, idxCols);
idx = ctx.indexProcessor().createIndex(cacheInfo.cacheContext(), new
ClientIndexFactory(), def);
// Here inline size is just for information (to be shown in system view).
inlineSize = InlineIndexTree.computeInlineSize(
idxFullName.fullName(),
InlineIndexKeyTypeRegistry.types(idxCols.values(), new
IndexKeyTypeSettings()),
new ArrayList<>(idxCols.values()),
idxDesc.inlineSize(),
tbl.cacheInfo().config().getSqlIndexMaxInlineSize(),
log
);{code}
You propose to remove forced limit and just print warning, yes? And only on
SERVER nodes, I suppose - then we can use real page size. *But users will
likely check log only after encountering problems*
>> Then this also might happen with 2 entries also, but less likely. Am I
>> correct?
If we have 2 child entries per node and 128 levels limit, I assume we would
need 2^128 entries to cause problems
was (Author: JIRAUSER303902):
[~timonin.maksim] Client nodes calculate inline size (for INDEXES system view):
{code:java}
ClientIndexDefinition def = new ClientIndexDefinition(idxFullName, idxCols);
idx = ctx.indexProcessor().createIndex(cacheInfo.cacheContext(), new
ClientIndexFactory(), def);
// Here inline size is just for information (to be shown in system view).
inlineSize = InlineIndexTree.computeInlineSize(
idxFullName.fullName(),
InlineIndexKeyTypeRegistry.types(idxCols.values(), new
IndexKeyTypeSettings()),
new ArrayList<>(idxCols.values()),
idxDesc.inlineSize(),
tbl.cacheInfo().config().getSqlIndexMaxInlineSize(),
log
);{code}
You propose to remove forced limit and just print warning, yes? And only on
SERVER nodes, I suppose - then we can use real page size
>> Then this also might happen with 2 entries also, but less likely. Am I
>> correct?
If we have 2 child entries per node and 128 levels limit, I assume we would
need 2^128 entries to cause problems
> Improve inline index feature
> ----------------------------
>
> Key: IGNITE-23120
> URL: https://issues.apache.org/jira/browse/IGNITE-23120
> Project: Ignite
> Issue Type: Improvement
> Reporter: Vladimir Pligin
> Assignee: Philipp Shergalis
> Priority: Major
>
> Ignite allows index rows to be inlined directly into the page. However, it
> doesn’t guard properly against too big inline size values. Currently, it uses
> {{PageIO.MAX_PAYLOAD_SIZE}} as the maximum allowed value, but this value can
> still be too large, because it does not take the page size and encryption
> (which adds additional bytes to the page header) into account. This possibly
> leads to a bad situation when only one item can fit in one page which can
> lead to BTree performance degradation.
> The following is expected to be done:
> # When inline size for an index is set, a maximum inline size should be
> computed:
> ## Considering we want to have _at least_ 2 items per page, here’s how the
> page layout with max inline size will look like: {{PS = H + L + I + L + I +
> L}} . Where PS - Page Size, H - page header size, L - size of the child link,
> I - item size.
> ## Using the above equation, we get the max possible item size to be equal
> to: {{I = (PS - H - 3L) / 2}} . However, for inline indexes, every item has
> an additional overhead to the actual inlined value (a.k.a payload), which
> depends on MVCC being present.
> ## Taking this into account, the maximum payload size will be equal: {{P =
> (PS - H - 3L) / 2 - X}} , where P - Payload size, X - overhead per item.
> ## In implementation terms, {{PS}} must be computed using the
> {{PageMemory#realPageSize}} which takes encryption overhead into
> account,{{{}H{}}} is equal to {{{}BPlusIo#ITEMS_OFF{}}}, {{L}} is 8 bytes and
> {{X}} depends on the actual {{AbstractH2ExtrasInnerIO}} implementation and
> varies between 8 and 28 bytes.
> # If the configured inline size exceeds the computed maximum size or
> {{PageIO.MAX_PAYLOAD_SIZE}} then an exception must be thrown with a message
> that notifies the user of the incorrect inline size value. Note that this
> should only happen for _new_ indexes, if a nodes is started on top of an
> existing PDS, no exceptions should be thrown and a warning should be printed
> instead, to preserve backwards compatibility.
> # Fix the “Indexed columns of a row cannot be fully inlined into index”
> warning to recommend at most the maximum allowed inline size.
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