[
https://issues.apache.org/jira/browse/DERBY-3116?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12534775
]
Jørgen Løland commented on DERBY-3116:
--------------------------------------
Hi Knut Anders.
Patch d3116-1 looks correct to me, but it seems a little overkill to always
reinitiate the byte[] in StoredPage. Could you achieve the same thing by moving
the initSpace call from StoredPage#usePageBuffer to StoredPage#createPage?
Alternatively make initSpace protected and call StoredPage#initSpace from
CachedPage#setPageArray when the page is reused?
Another bug? In StoredPage#initSpace, slotEntrySize is used when setting
maxFieldSize. However, initSpace is called before slotEntrySize has been
updated in usePageBuffer.
Not related to your patch: There is a problem with the Javadoc in AllocPage
(unclosed paragraph "<p"). Fixing that would show more javadoc in the html
files.
> totalSpace not properly initialized in AllocPage
> ------------------------------------------------
>
> Key: DERBY-3116
> URL: https://issues.apache.org/jira/browse/DERBY-3116
> Project: Derby
> Issue Type: Bug
> Components: Store
> Affects Versions: 10.4.0.0
> Reporter: Knut Anders Hatlen
> Priority: Minor
> Attachments: d3116-1.diff
>
>
> There are some problems with the initialization of totalSpace in AllocPage.
> It is initialized in StoredPage.initSpace() which is again called from
> StoredPage.usePageBuffer(), and it is set to the value returned from
> AllocPage.getMaxFreeSpace(). The problems are:
> 1) The calculation in getMaxFreeSpace() uses borrowedSpace, but when
> createIdentity() is called on an AllocPage, borrowedSpace has not been
> initialized when getMaxFreeSpace() is called and the calculated size is wrong.
> 2) When a page object is reused, usePageBuffer() is only called if a new
> byte array must be allocated (because the new page has a different size than
> the old page). This means that the totalSize field gets the same value as in
> the old page if their sizes are equal, which is not necessarily correct.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
