Measure-DbaDbVirtualLogFile.html

﻿<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>dbatools docs | Measure-DbaDbVirtualLogFile</title>
    <link rel="icon" href="https://dbatools.io/wp-content/uploads/2016/05/dbatools.png" sizes="32x32">
    <link rel="icon" href="https://dbatools.io/wp-content/uploads/2016/05/dbatools.png" sizes="192x192">
    <link rel="apple-touch-icon-precomposed" href="https://dbatools.io/wp-content/uploads/2016/05/dbatools.png">
    <meta name="msapplication-TileImage" content="https://dbatools.io/wp-content/uploads/2016/05/dbatools.png">

    <link title="Search" rel="search" type="application/opensearchdescription+xml" href="/opensearch.xml">
    <meta name="keywords" content="dbatools, ,powershell,sql server,devops,json">
    <meta name="subtitle" content="Docs for Measure-DbaDbVirtualLogFile">
    <meta property="og:type" content="article" />
    <meta property="og:title" content="dbatools docs:  Measure-DbaDbVirtualLogFile" />
    <meta property="og:url" content="https://docs.dbatools.io/Measure-DbaDbVirtualLogFile.html" />
    <meta property="og:description" content="dbatools docs for Measure-DbaDbVirtualLogFile" />
    <meta property="og:site_name" content="docs.dbatools.io" />
    <meta property="og:locale" content="en_US" />
    <meta name="twitter:text:title" content="dbatools docs:  Measure-DbaDbVirtualLogFile" />
    
    <meta name="twitter:image" content="https://docs.dbatools.io/assets/thumbs/Measure-DbaDbVirtualLogFile.png">
    <meta name="twitter:card" content="summary_large_image">
    
    <meta name=twitter:creator content="@psdbatools">
    <meta name=twitter:title content="dbatools docs:  Measure-DbaDbVirtualLogFile">
    <meta property="twitter:site" content="@psdbatools" />

    <meta property="og:image" content="https://docs.dbatools.io/assets/thumbs/Measure-DbaDbVirtualLogFile.png">
    <link rel=canonical href="https://docs.dbatools.io/Measure-DbaDbVirtualLogFile.html" />
    <link rel=alternate type=application/json
        href=https://raw.githubusercontent.com/dataplat/dbatools/master/bin/dbatools-index.json
        title="dbatools documentation">

    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"
        integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
    <link rel="stylesheet" type="text/css"
        href="//cdnjs.cloudflare.com/ajax/libs/open-iconic/1.1.1/font/css/open-iconic-bootstrap.min.css">
    <link rel="stylesheet" type="text/css"
        href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/github.min.css">

    <link rel="stylesheet" href="assets/css/layout.css">
    <!-- Global site tag (gtag.js) - Google Analytics -->
    <script async src="https://www.googletagmanager.com/gtag/js?id=UA-80639740-2"></script>
    <script>
        window.dataLayer = window.dataLayer || [];
        function gtag() { dataLayer.push(arguments); }
        gtag('js', new Date());

        gtag('config', 'UA-80639740-2');
    </script>


    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"
        integrity="sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy"
        crossorigin="anonymous"></script>
    <script src="//cdn.jsdelivr.net/npm/lodash@4.17.4/lodash.min.js"></script>
    <script src="//cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/highlight.min.js"></script>
    <script src="//cdn.jsdelivr.net/jquery.scrollto/2.1.2/jquery.scrollTo.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/list.js/1.5.0/list.min.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/autolinker/1.7.1/Autolinker.js"></script>
    <script src="//cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.0/clipboard.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/jqcloud2@2.0.3/dist/jqcloud.min.js"
        integrity="sha256-+krhsKJpvd3AZYVGHcwyCUGO01uNdGSTvqR7Apcy30E=" crossorigin="anonymous"></script>

    <script type="text/javascript" language="javascript">
        function register_dbatools_hljs(dbatoolscommands) {

            hljs.registerLanguage("powershell", function (e) {
                var t = {
                    b: "`[\\s\\S]",
                    r: 0
                },
                    o = {
                        cN: "variable",
                        v: [{
                            b: /\$[\w\d][\w\d_:]*/
                        }]
                    },
                    r = {
                        cN: "literal",
                        b: /\$(null|true|false)\b/
                    },
                    n = {
                        cN: "string",
                        v: [{
                            b: /"/,
                            e: /"/
                        }, {
                            b: /@"/,
                            e: /^"@/
                        }],
                        c: [t, o, {
                            cN: "variable",
                            b: /\$[A-z]/,
                            e: /[^A-z]/
                        }]
                    },
                    a = {
                        cN: "string",
                        v: [{
                            b: /'/,
                            e: /'/
                        }, {
                            b: /@'/,
                            e: /^'@/
                        }]
                    },
                    i = {
                        cN: "doctag",
                        v: [{
                            b: /\.(synopsis|description|example|inputs|outputs|notes|link|component|role|functionality)/
                        }, {
                            b: /\.(parameter|forwardhelptargetname|forwardhelpcategory|remotehelprunspace|externalhelp)\s+\S+/
                        }]
                    },
                    s = e.inherit(e.C(null, null), {
                        v: [{
                            b: /#/,
                            e: /$/
                        }, {
                            b: /<#/,
                            e: /#>/
                        }],
                        c: [i]
                    });
                return {
                    aliases: ["ps"],
                    l: /-?[A-z\.\-]+/,
                    cI: !0,
                    k: {
                        keyword: "if else foreach return function do while until elseif begin for trap data dynamicparam end break throw param continue finally in switch exit filter try process catch",
                        built_in: dbatoolscommands + " Add-Computer Add-Content Add-History Add-JobTrigger Add-Member Add-PSSnapin Add-Type Checkpoint-Computer Clear-Content Clear-EventLog Clear-History Clear-Host Clear-Item Clear-ItemProperty Clear-Variable Compare-Object Complete-Transaction Connect-PSSession Connect-WSMan Convert-Path ConvertFrom-Csv ConvertFrom-Json ConvertFrom-SecureString ConvertFrom-StringData ConvertTo-Csv ConvertTo-Html ConvertTo-Json ConvertTo-SecureString ConvertTo-Xml Copy-Item Copy-ItemProperty Debug-Process Disable-ComputerRestore Disable-JobTrigger Disable-PSBreakpoint Disable-PSRemoting Disable-PSSessionConfiguration Disable-WSManCredSSP Disconnect-PSSession Disconnect-WSMan Disable-ScheduledJob Enable-ComputerRestore Enable-JobTrigger Enable-PSBreakpoint Enable-PSRemoting Enable-PSSessionConfiguration Enable-ScheduledJob Enable-WSManCredSSP Enter-PSSession Exit-PSSession Export-Alias Export-Clixml Export-Console Export-Counter Export-Csv Export-FormatData Export-ModuleMember Export-PSSession ForEach-Object Format-Custom Format-List Format-Table Format-Wide Get-Acl Get-Alias Get-AuthenticodeSignature Get-ChildItem Get-Command Get-ComputerRestorePoint Get-Content Get-ControlPanelItem Get-Counter Get-Credential Get-Culture Get-Date Get-Event Get-EventLog Get-EventSubscriber Get-ExecutionPolicy Get-FormatData Get-Host Get-HotFix Get-Help Get-History Get-IseSnippet Get-Item Get-ItemProperty Get-Job Get-JobTrigger Get-Location Get-Member Get-Module Get-PfxCertificate Get-Process Get-PSBreakpoint Get-PSCallStack Get-PSDrive Get-PSProvider Get-PSSession Get-PSSessionConfiguration Get-PSSnapin Get-Random Get-ScheduledJob Get-ScheduledJobOption Get-Service Get-TraceSource Get-Transaction Get-TypeData Get-UICulture Get-Unique Get-Variable Get-Verb Get-WinEvent Get-WmiObject Get-WSManCredSSP Get-WSManInstance Group-Object Import-Alias Import-Clixml Import-Counter Import-Csv Import-IseSnippet Import-LocalizedData Import-PSSession Import-Module Invoke-AsWorkflow Invoke-Command Invoke-Expression Invoke-History Invoke-Item Invoke-RestMethod Invoke-WebRequest Invoke-WmiMethod Invoke-WSManAction Join-Path Limit-EventLog Measure-Command Measure-Object Move-Item Move-ItemProperty New-Alias New-Event New-EventLog New-IseSnippet New-Item New-ItemProperty New-JobTrigger New-Object New-Module New-ModuleManifest New-PSDrive New-PSSession New-PSSessionConfigurationFile New-PSSessionOption New-PSTransportOption New-PSWorkflowExecutionOption New-PSWorkflowSession New-ScheduledJobOption New-Service New-TimeSpan New-Variable New-WebServiceProxy New-WinEvent New-WSManInstance New-WSManSessionOption Out-Default Out-File Out-GridView Out-Host Out-Null Out-Printer Out-String Pop-Location Push-Location Read-Host Receive-Job Register-EngineEvent Register-ObjectEvent Register-PSSessionConfiguration Register-ScheduledJob Register-WmiEvent Remove-Computer Remove-Event Remove-EventLog Remove-Item Remove-ItemProperty Remove-Job Remove-JobTrigger Remove-Module Remove-PSBreakpoint Remove-PSDrive Remove-PSSession Remove-PSSnapin Remove-TypeData Remove-Variable Remove-WmiObject Remove-WSManInstance Rename-Computer Rename-Item Rename-ItemProperty Reset-ComputerMachinePassword Resolve-Path Restart-Computer Restart-Service Restore-Computer Resume-Job Resume-Service Save-Help Select-Object Select-String Select-Xml Send-MailMessage Set-Acl Set-Alias Set-AuthenticodeSignature Set-Content Set-Date Set-ExecutionPolicy Set-Item Set-ItemProperty Set-JobTrigger Set-Location Set-PSBreakpoint Set-PSDebug Set-PSSessionConfiguration Set-ScheduledJob Set-ScheduledJobOption Set-Service Set-StrictMode Set-TraceSource Set-Variable Set-WmiInstance Set-WSManInstance Set-WSManQuickConfig Show-Command Show-ControlPanelItem Show-EventLog Sort-Object Split-Path Start-Job Start-Process Start-Service Start-Sleep Start-Transaction Start-Transcript Stop-Computer Stop-Job Stop-Process Stop-Service Stop-Transcript Suspend-Job Suspend-Service Tee-Object Test-ComputerSecureChannel Test-Connection Test-ModuleManifest Test-Path Test-PSSessionConfigurationFile Trace-Command Unblock-File Undo-Transaction Unregister-Event Unregister-PSSessionConfiguration Unregister-ScheduledJob Update-FormatData Update-Help Update-List Update-TypeData Use-Transaction Wait-Event Wait-Job Wait-Process Where-Object Write-Debug Write-Error Write-EventLog Write-Host Write-Output Write-Progress Write-Verbose Write-Warning Add-MDTPersistentDrive Disable-MDTMonitorService Enable-MDTMonitorService Get-MDTDeploymentShareStatistics Get-MDTMonitorData Get-MDTOperatingSystemCatalog Get-MDTPersistentDrive Import-MDTApplication Import-MDTDriver Import-MDTOperatingSystem Import-MDTPackage Import-MDTTaskSequence New-MDTDatabase Remove-MDTMonitorData Remove-MDTPersistentDrive Restore-MDTPersistentDrive Set-MDTMonitorData Test-MDTDeploymentShare Test-MDTMonitorData Update-MDTDatabaseSchema Update-MDTDeploymentShare Update-MDTLinkedDS Update-MDTMedia Update-MDTMedia Add-VamtProductKey Export-VamtData Find-VamtManagedMachine Get-VamtConfirmationId Get-VamtProduct Get-VamtProductKey Import-VamtData Initialize-VamtData Install-VamtConfirmationId Install-VamtProductActivation Install-VamtProductKey Update-VamtProduct",
                        nomarkup: "-ne -eq -lt -gt -ge -le -not -like -notlike -match -notmatch -contains -notcontains -in -notin -replace"
                    },
                    c: [t, e.NM, n, a, r, o, s]
                }
            });

        }
        $(document).ready(function () {
            function render_doc(doc_to_render, examples_mode) {
                
                $("#rendered h5").each(function (i, el) {
                    if ($(el).text().startsWith('-')) {
                        $(el).addClass('param')
                    }
                })
                $('#rendered table').addClass('table table-sm table-hover')
                if (examples_mode == 'new') {
                    $('#rendered code').addClass('powershell')
                }
                $('#rendered code').each(function (i, block) {
                    hljs.highlightBlock(block);
                })
                var authorcontent = $("td:contains('Author')").next('td').addClass('dbatools_author').text()
                $("#rendered .dbatools_author").html(Autolinker.link(authorcontent, {
                    className: 'myLink',
                    mention: 'twitter'
                })
                )
                $("#rendered h2#syntax").next().find('code').addClass('wrapped')
                if (ClipboardJS.isSupported()) {
                    $("#rendered h5[id^='example-']").append('<div class="bd-clipboard"><button class="btn-clipboard" title="Copy to clipboard">Copy</button></div>')
                    new ClipboardJS('.btn-clipboard', {
                        text: function (trigger) {
                            var textlines = $(trigger).parent().parent().next('pre').find('code').text().split('\n')
                            var copied = []
                            _.forEach(textlines, function (row) {
                                copied.push(row.replace(/^PS C:\\> /, "").replace(/^>>/, ""))
                            })
                            return _.join(copied, '\n')
                        }
                    });
                }


                //not all code is a block 
                $("#rendered h3[id*='-parameters']").nextAll().find('code').addClass('hljs-inline')
                $('#rendered #description').nextUntil('#rendered #syntax').find('code').addClass('hljs-inline')
            }

            $('#loader').removeClass('invisible')
            var index_url = 'assets/dbatools-index.json'
            var external_url = 'assets/external.json'
            var values = [];
            var options = {
                valueNames: ['CommandName', 'Description', 'Alias', 'Examples', 'Params'],
                item: '<a class="list-group-item" href="#"><span class="CommandName"></span></a>'
            }
            cmdlist = new List('cmdlist', options, values);
            var indexhelp = ''
            var allcmds = $.getJSON(index_url, function (data) {
                indexhelp = data
                cmdlist.add(data)
                var dbacommands = []
                var cloudlist = {}
                _.forEach(data, function (el) {
                    dbacommands.push(el.CommandName)
                    if (_.isArray(el.Tags)) {
                        _.forEach(el.Tags, function (el) {
                            if (!_.has(cloudlist, el)) {
                                cloudlist[el] = 0
                            }
                            cloudlist[el] += 1
                        })
                    } else if (!_.isUndefined(el.Tags)){
                        if (!_.has(cloudlist, el.Tags)) {
                            cloudlist[el.Tags] = 0
                        }
                        cloudlist[el.Tags] += 1
                    }
                })
                var weightedVals = []
                _.forEach(cloudlist, function (value, key) {
                    weightedVals.push({
                        text: key,
                        weight: value,
                        handlers: {
                            click: function () { $('#search-ft').val('tag:' + key).trigger('keyup') }
                        }
                    })
                })
                var pixelHeight = window.innerHeight * 0.65;
                $('#canvas').css({ 'height': pixelHeight + 'px' });
                $('#canvas').jQCloud(weightedVals, {
                    autoResize: true
                });

                register_dbatools_hljs(dbacommands.join(' '))
                $(window).trigger('hashchange');
            })
            var options2 = {
                valueNames: ['extName', { name: 'extHref', attr: 'href' }],
                item: '<div><a class="list-group-item list-group-item-secondary extHref" href="#" _target="_blank"><span class="extName"></span></a></div>'
            }
            extlist = new List('extlist', options2, [])

            $.getJSON(external_url, function (data) {
                $('#dbatools_version').text('(v ' + data.version + ')')
                _.forEach(data.external_links, function (el) {
                    extlist.add({ 'extName': el.name, 'extHref': el.href })
                })
            })
            cmdlist.on('searchComplete', function (e) {
                if (cmdlist.matchingItems.length === 0) {
                    var searchString = $('#search-ft').val().trim();
                    if (searchString.length > 0 && !searchString.startsWith("ft:")) {
                        if (searchString != "f" && searchString != "ft" && searchString != "ft:") {
                            $('#search-ft').val("ft:" + searchString)
                        }
                    }
                }
            })
            $(document).on('mouseenter', '#cmdlist', function (e) {
                $('#search-ft').blur();
            })
            cmdlist.on('updated', function() {
                $('#cmdlist a').each(function(i, el) {
                    $(el).attr('href', $(el).find('span.CommandName').text())
                })
            })
            $('#cmdlist').on('mouseenter', 'a', function (e) {
                $(this).attr('href', $(this).find('span.CommandName').text());
                /*
                e.preventDefault();
                window.location.href = $(this).find('span.CommandName').text()
                ---
                window.location.hash = '#' + $(this).find('span.CommandName').text();
                $('#cmdlist').find('a.active').removeClass('active')
                $(this).addClass('active')
                */
            })
            $('#search-ft').bind('change keyup', function () {
                var searchString = $(this).val();
                if (searchString.trim() == "ft:" || searchString.trim() == "tag:") {
                    extlist.search();
                }
                else if (searchString.startsWith("ft:")) {
                    searchString = searchString.substring(3).trim();
                    if (cmdlist.filtered) {
                        cmdlist.filter();
                    }
                    cmdlist.search(searchString, ['CommandName', 'Alias', 'Description', 'Synopsis', 'Examples', 'Params']);
                } else if (searchString.startsWith("tag:")) {
                    searchString = searchString.substring(4).trim();
                    if (cmdlist.searched) {
                        cmdlist.search();
                    }
                    cmdlist.filter(function (item) {
                        if (_.indexOf(item.values().Tags, searchString) !== -1) {
                            return true;
                        } else {
                            return false;
                        }
                    });
                } else {
                    if (cmdlist.filtered) {
                        cmdlist.filter();
                    }
                    cmdlist.search(searchString, ['CommandName', 'Alias']);
                }
                extlist.search('$$$')
                if (_.isEmpty(searchString)) {
                    extlist.search()
                    cmdlist.filter()
                }
            })
            $('#clear-search').on('click', function () {
                $('#search-ft').val('').trigger('keyup')
            })
            $(window).on('hashchange', function (e) {
                var hash = window.location.hash.substr(1);
                var pagename = window.location.pathname.split("/").filter(function (c) { return c.length; }).pop();
                if (_.isUndefined(pagename)) {
                    pagename = ''
                } else {
                    pagename = pagename.split('.')[0];
                }
                if (hash.length == 0) {
                    hash = pagename
                }
                if (hash.length > 0) {
                    //ends with /
                    if (_.endsWith(hash, '/')) {
                        window.location.hash = '#' + hash.slice(0, hash.length - 1)
                        $(window).trigger('hashchange');
                        return;
                    }
                    //exact match
                    var topublish = _.findIndex(indexhelp, { 'Name': hash })
                    if (topublish == -1) {
                        //lowercase match
                        var topublish = _.findIndex(indexhelp, function (el) { return _.toLower(el.Name) == _.toLower(hash) })
                        if (topublish == -1) {
                            //alias match
                            var topublish = _.findIndex(indexhelp, { 'Alias': hash })
                            if (topublish == -1) {
                                //lowercase alias match
                                var topublish = _.findIndex(indexhelp, function (el) { return _.toLower(el.Alias) == _.toLower(hash) })
                            }
                            if (topublish == -1) {
                                //multiple aliases, optionally lowercased
                                var topublish = _.findIndex(indexhelp, function (el) { return _.includes(_.toLower(el.Alias).split(','), _.toLower(hash)) })
                            }
                        }
                        if (topublish !== -1) {
                            //normalization of URI
                            window.location.hash = '#' + indexhelp[topublish].CommandName
                            $(window).trigger('hashchange')
                            return;
                        }
                    }
                    if (topublish == -1) {
                        $('#rendered').html(marked.parse('### 404 Function not found \n (while searching for ' + hash + '). Please visit dbatools.io/commands for an updated index of current commands.'));
                    } else {
                        var doc_to_render = indexhelp[topublish]
                        render_doc(doc_to_render, 'new')
                        $("body").data("doc_to_render", indexhelp[topublish])
                        if ($("#headscroll").offset().top > 150) {
                            $(window).scrollTo('#headscroll')
                        } else {
                            $(window).scrollTo(0, 800)
                        }
                    }
                } else {
                    $('#loader').addClass('invisible')
                }
            })
            $(window).scroll(function () {
                if ($(this).scrollTop() > 50) {
                    $('#back-to-top').fadeIn();
                } else {
                    $('#back-to-top').fadeOut();
                }
            })
            $('#back-to-top').click(function () {
                $(window).scrollTo(0, 800)
                return false;
            })

        })
    </script>
</head>


<body>

    <nav class="navbar navbar-expand-md customnav">
        <a href="https://docs.dbatools.io/" class="navbar-brand" rel="home" itemprop="url">
            <img width="265" height="64" src="https://dbatools.io/wp-content/uploads/2018/09/dbatools-docs.png"
                class="custom-logo" alt="dbatools" itemprop="logo" scale="0">
        </a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse"
            aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
            <span class="oi oi-menu"></span>
        </button>
        <div class="collapse navbar-collapse flex-grow-1 text-right" id="navbarCollapse">
            <ul class="navbar-nav ml-auto flex-nowrap">
                <li class="nav-item">
                    <a class="nav-link" style="color:#293E5D" href="https://dbatools.io/download/">⬇ download</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" style="color:#293E5D" href="https://dbatools.io/commands/">🚀 commands</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" style="color:#293E5D" href="https://dbatools.io/slack">🔍 find us</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" style="color:#293E5D" href="https://dbatools.io/builds">🔢 build ref</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" style="color:#293E5D" href="https://dbatools.io/book">📘 dbatools book</a>
                </li>
            </ul>
        </div>
    </nav>

    <div class="container-fluid">
        <div class="row">
            <div class="col-md-12">
                <hr />
            </div>
        </div>
        <div class="row">
            <div class="col-xl-3 col-lg-5 col-md-5 col-sm-12 bd-sidebar">
                <div id="relcommands" class="">
                    <h3>
                        commands
                        <small id="dbatools_version" class="text-muted"></small>
                    </h3>
                    <p></p>
                    <div class="form-group row">
                        <div class="col-lg-12">
                            <div class="input-group">

                                <input type="text" class="form-control" id="search-ft"
                                    placeholder="Search (&quot;ft: term&quot; enables fulltext)" autocomplete="off">
                                <div class="input-group-append">
                                    <div class="input-group-text" id="clear-search">Clear</div>
                                </div>
                            </div>
                        </div>
                    </div>
                    <div id="extlist">
                        <div class="list list-group"></div>
                    </div>
                    <div id="cmdlist">
                        <div class="list list-group"></div>
                    </div>
                </div>
            </div>
            <div class="col-xl-9 col-lg-7 col-md-7 col-sm-12 bd-content">
                <div id="headscroll">
                    <a id="back-to-top" href="#" class="btn btn-primary btn-lg back-to-top" role="button"
                        title="Click to return on the top page">&#94;</a>
                </div>
                <div id="rendered">
                    <h1 id="measure-dbadbvirtuallogfile">Measure-DbaDbVirtualLogFile</h1>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td><strong>Author</strong></td>
<td>Chrissy LeMaire (@cl), netnerds.net</td>
</tr>
<tr>
<td><strong>Availability</strong></td>
<td>Windows, Linux, macOS</td>
</tr>
</tbody>
</table>
<p> </p>
<p>Want to see the source code for this command? Check out <a href="https://github.com/dataplat/dbatools/blob/master/public/Measure-DbaDbVirtualLogFile.ps1">Measure-DbaDbVirtualLogFile</a> on GitHub.
<br>
Want to see the Bill Of Health for this command? Check out <a href="https://dataplat.github.io/boh#Measure-DbaDbVirtualLogFile">Measure-DbaDbVirtualLogFile</a>.</p>
<h2 id="synopsis">Synopsis</h2>
<p>Returns calculations on the database virtual log files for database on a SQL instance.</p>
<h2 id="description">Description</h2>
<p>Having a transaction log file with too many virtual log files (VLFs) can hurt database performance.</p>
<p>Too many VLFs can cause transaction log backups to slow down and can also slow down database recovery and, in extreme cases, even affect insert/update/delete performance.</p>
<p>References:<br />
<a href="http://www.sqlskills.com/blogs/kimberly/transaction-log-vlfs-too-many-or-too-few/">http://www.sqlskills.com/blogs/kimberly/transaction-log-vlfs-too-many-or-too-few/</a><br />
<a href="http://blogs.msdn.com/b/saponsqlserver/archive/2012/02/22/too-many-virtual-log-files-vlfs-can-cause-slow-database-recovery.aspx">http://blogs.msdn.com/b/saponsqlserver/archive/2012/02/22/too-many-virtual-log-files-vlfs-can-cause-slow-database-recovery.aspx</a></p>
<p>If you've got a high number of VLFs, you can use Expand-SqlTLogResponsibly to reduce the number.</p>
<h2 id="syntax">Syntax</h2>
<pre><code>Measure-DbaDbVirtualLogFile
    [-SqlInstance] &lt;DbaInstanceParameter[]&gt;
    [[-SqlCredential] &lt;PSCredential&gt;]
    [[-Database] &lt;Object[]&gt;]
    [[-ExcludeDatabase] &lt;Object[]&gt;]
    [-IncludeSystemDBs]
    [-EnableException]
    [&lt;CommonParameters&gt;]

</code></pre>
<p> </p>
<h2 id="examples">Examples</h2>
<p> </p>
<h5 id="example-1">Example:  1</h5>
<pre><code>PS C:\&gt; Measure-DbaDbVirtualLogFile -SqlInstance sqlcluster
</code></pre>
<p>Returns all user database virtual log file counts for the sqlcluster instance.<br></p>
<h5 id="example-2">Example:  2</h5>
<pre><code>PS C:\&gt; Measure-DbaDbVirtualLogFile -SqlInstance sqlserver | Where-Object {$_.Total -ge 50}
</code></pre>
<p>Returns user databases that have 50 or more VLFs.<br></p>
<h5 id="example-3">Example:  3</h5>
<pre><code>PS C:\&gt; @('sqlserver','sqlcluster') | Measure-DbaDbVirtualLogFile
</code></pre>
<p>Returns all VLF information for the sqlserver and sqlcluster SQL Server instances. Processes data via the pipeline.<br></p>
<h5 id="example-4">Example:  4</h5>
<pre><code>PS C:\&gt; Measure-DbaDbVirtualLogFile -SqlInstance sqlcluster -Database db1, db2
</code></pre>
<p>Returns VLF counts for the db1 and db2 databases on sqlcluster.<br></p>
<h3 id="required-parameters">Required Parameters</h3>
<h5 id="sqlinstance">-SqlInstance</h5>
<p>The target SQL Server instance or instances. <br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>True</td>
</tr>
<tr>
<td>Pipeline</td>
<td>true (ByValue)</td>
</tr>
<tr>
<td>Default Value</td>
<td></td>
</tr>
</tbody>
</table>
<h3 id="optional-parameters">Optional Parameters</h3>
<h5 id="sqlcredential">-SqlCredential</h5>
<p>Login to the target instance using alternative credentials. Accepts PowerShell credentials (Get-Credential).<br />
Windows Authentication, SQL Server Authentication, Active Directory - Password, and Active Directory - Integrated are all supported.<br />
For MFA support, please use Connect-DbaInstance.<br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>False</td>
</tr>
<tr>
<td>Pipeline</td>
<td>false</td>
</tr>
<tr>
<td>Default Value</td>
<td></td>
</tr>
</tbody>
</table>
<h5 id="database">-Database</h5>
<p>Specifies the database(s) to process. Options for this list are auto-populated from the server. If unspecified, all databases will be processed.<br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>False</td>
</tr>
<tr>
<td>Pipeline</td>
<td>false</td>
</tr>
<tr>
<td>Default Value</td>
<td></td>
</tr>
</tbody>
</table>
<h5 id="excludedatabase">-ExcludeDatabase</h5>
<p>Specifies the database(s) to exclude from processing. Options for this list are auto-populated from the server.<br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>False</td>
</tr>
<tr>
<td>Pipeline</td>
<td>false</td>
</tr>
<tr>
<td>Default Value</td>
<td></td>
</tr>
</tbody>
</table>
<h5 id="includesystemdbs">-IncludeSystemDBs</h5>
<p>If this switch is enabled, system database information will be displayed.<br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>False</td>
</tr>
<tr>
<td>Pipeline</td>
<td>false</td>
</tr>
<tr>
<td>Default Value</td>
<td>False</td>
</tr>
</tbody>
</table>
<h5 id="enableexception">-EnableException</h5>
<p>By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.<br />
This avoids overwhelming you with &quot;sea of red&quot; exceptions, but is inconvenient because it basically disables advanced scripting.<br />
Using this switch turns this &quot;nice by default&quot; feature off and enables you to catch exceptions with your own try/catch.<br></p>
<table>
<thead>
<tr>
<th></th>
<th></th>
</tr>
</thead>
<tbody>
<tr>
<td>Alias</td>
<td></td>
</tr>
<tr>
<td>Required</td>
<td>False</td>
</tr>
<tr>
<td>Pipeline</td>
<td>false</td>
</tr>
<tr>
<td>Default Value</td>
<td>False</td>
</tr>
</tbody>
</table>
<p> </p>

                </div> <!-- rendered -->
            </div>
        </div>
    </div>
</body>

</html>