When does SQL Server warn about an Excessive Memory Grant?
What are the conditions that produce an "Excessive Grant" execution plan warning?
The query memory grant detected "ExcessiveGrant", which may impact the reliability. Grant size: Initial 5128 KB, Final 5128 KB, Used 16 KB.
SSMS
Plan Explorer
Showplan xml
<Warnings>
<MemoryGrantWarning GrantWarningKind="Excessive Grant"
RequestedMemory="5128" GrantedMemory="5128" MaxUsedMemory="16" />
</Warnings>
sql-server execution-plan warning memory-grant
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
add a comment |
What are the conditions that produce an "Excessive Grant" execution plan warning?
The query memory grant detected "ExcessiveGrant", which may impact the reliability. Grant size: Initial 5128 KB, Final 5128 KB, Used 16 KB.
SSMS
Plan Explorer
Showplan xml
<Warnings>
<MemoryGrantWarning GrantWarningKind="Excessive Grant"
RequestedMemory="5128" GrantedMemory="5128" MaxUsedMemory="16" />
</Warnings>
sql-server execution-plan warning memory-grant
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
add a comment |
What are the conditions that produce an "Excessive Grant" execution plan warning?
The query memory grant detected "ExcessiveGrant", which may impact the reliability. Grant size: Initial 5128 KB, Final 5128 KB, Used 16 KB.
SSMS
Plan Explorer
Showplan xml
<Warnings>
<MemoryGrantWarning GrantWarningKind="Excessive Grant"
RequestedMemory="5128" GrantedMemory="5128" MaxUsedMemory="16" />
</Warnings>
sql-server execution-plan warning memory-grant
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
What are the conditions that produce an "Excessive Grant" execution plan warning?
The query memory grant detected "ExcessiveGrant", which may impact the reliability. Grant size: Initial 5128 KB, Final 5128 KB, Used 16 KB.
SSMS
Plan Explorer
Showplan xml
<Warnings>
<MemoryGrantWarning GrantWarningKind="Excessive Grant"
RequestedMemory="5128" GrantedMemory="5128" MaxUsedMemory="16" />
</Warnings>
sql-server execution-plan warning memory-grant
sql-server execution-plan warning memory-grant
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
asked Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
52.9k14281457
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
To produce this warning:
- The maximum used memory must be less than 5% of the granted memory; AND
- The query must use the regular (not small) resource semaphore
To use the regular resource semaphore the query must:
- Have granted memory over 5MB (5120 KB, 640 x 8KB pages); OR
- Have a total estimated plan cost of over 3 units and not be a trivial plan
Server version requirements:
- SQL Server 2014 SP2 (12.0.5000) or later
- SQL Server 2016 SP1 (13.0.4001) or later
- SQL Server 2017 RTM (14.0.1000) or later
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "182"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdba.stackexchange.com%2fquestions%2f228237%2fwhen-does-sql-server-warn-about-an-excessive-memory-grant%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
To produce this warning:
- The maximum used memory must be less than 5% of the granted memory; AND
- The query must use the regular (not small) resource semaphore
To use the regular resource semaphore the query must:
- Have granted memory over 5MB (5120 KB, 640 x 8KB pages); OR
- Have a total estimated plan cost of over 3 units and not be a trivial plan
Server version requirements:
- SQL Server 2014 SP2 (12.0.5000) or later
- SQL Server 2016 SP1 (13.0.4001) or later
- SQL Server 2017 RTM (14.0.1000) or later
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
add a comment |
To produce this warning:
- The maximum used memory must be less than 5% of the granted memory; AND
- The query must use the regular (not small) resource semaphore
To use the regular resource semaphore the query must:
- Have granted memory over 5MB (5120 KB, 640 x 8KB pages); OR
- Have a total estimated plan cost of over 3 units and not be a trivial plan
Server version requirements:
- SQL Server 2014 SP2 (12.0.5000) or later
- SQL Server 2016 SP1 (13.0.4001) or later
- SQL Server 2017 RTM (14.0.1000) or later
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
add a comment |
To produce this warning:
- The maximum used memory must be less than 5% of the granted memory; AND
- The query must use the regular (not small) resource semaphore
To use the regular resource semaphore the query must:
- Have granted memory over 5MB (5120 KB, 640 x 8KB pages); OR
- Have a total estimated plan cost of over 3 units and not be a trivial plan
Server version requirements:
- SQL Server 2014 SP2 (12.0.5000) or later
- SQL Server 2016 SP1 (13.0.4001) or later
- SQL Server 2017 RTM (14.0.1000) or later
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
To produce this warning:
- The maximum used memory must be less than 5% of the granted memory; AND
- The query must use the regular (not small) resource semaphore
To use the regular resource semaphore the query must:
- Have granted memory over 5MB (5120 KB, 640 x 8KB pages); OR
- Have a total estimated plan cost of over 3 units and not be a trivial plan
Server version requirements:
- SQL Server 2014 SP2 (12.0.5000) or later
- SQL Server 2016 SP1 (13.0.4001) or later
- SQL Server 2017 RTM (14.0.1000) or later
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
edited Jan 31 at 9:21
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
answered Jan 28 at 12:15
Paul White♦Paul White
52.9k14281457
52.9k14281457
add a comment |
add a comment |
Thanks for contributing an answer to Database Administrators Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdba.stackexchange.com%2fquestions%2f228237%2fwhen-does-sql-server-warn-about-an-excessive-memory-grant%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
